Network+ Ch.4, Modern Ethernet

What is a big advantage to using fiber-optic cable? Fiber is common glass; therefore, it's less expensive. Fiber is not affected by EMI. Making custom cable lengths is easier with fiber. All that orange fiber looks impressive in the network closet.

B

What standard does IEEE 802.3ab describe? 1000BaseLX 1000BaseT 100BaseT 1000BaseSX

B

100BaseFX Summary: Signal type

Baseband

100BaseT Summary: Signal type

Baseband

BiDi stands for

Bidirectional

10GBaseT: Cabling, Wavelength / Cable Details, Connectors, Length

Cabling: Cat 6/6a UTP. Wavelength / Cable Details: Four-pair/full-duplex. Connectors: RJ-45. Length: 55/100 m

1000BaseT: :Cabling, Cable Details, Connectors, Length:

Cabling: Cat5e/6 UTP. Cable details: Four-pair/full-duplex. Connectors: RJ-45. Length: 100m

1000BaseLX:Cabling, Cable Details, Connectors, Length:

Cabling: Single-mode fiber. Cable details: 1300 nm. Connectors: Variable, commonly LC and SC. Length: 5km

1000BaseSX: Cabling, Cable Details, Connectors, Length:

Cabling: multimode fiber. Cable details: 850 nm. Connectors: variable, commonly LC. Length: 220-500m.

10GBaseSR/SW: Cabling, Wavelength / Cable Details, Connectors, Length

Cabling: multimode fiber. Wavelength / Cable Details: 850 nm. Connectors: not defined, Length: 26-300 m

10GBaseLR/LW: Cabling, Wavelength / Cable Details, Connectors, Length

Cabling: single-mode fiber. Wavelength / Cable Details: 1310 nm. Connectors: variable, commonly LC. Length: 10km

10GBaseER/EW: Cabling, Wavelength / Cable Details, Connectors, Length

Cabling: single-mode fiber. Wavelength / Cable Details: 1550 nm. Connectors: variable, commonly LC and SC. Length: 40km

Cat of cable that 100BaseT4 used

Cat 3

10 Gigabit Ethernet (__) offers speeds of up to 10 gigabits per second, as its name indicates.

10 GbE

10GBaseLy uses a long-wavelength (1310 nm) signal over single-mode fiber. The maximum fiber length is

10 kilometers, although this length will vary depending on the type of single-mode fiber used.

10GBaseLR/LW: Length

10 km

Standard 10GBaseLR: Maximum Signal Length

10 km

Standard 10GBaseLW: Maximum Signal Length

10 km

100BaseFX Summary: Speed

100 Mbps

100BaseT Summary: Speed

100 Mbps

100BaseFX Summary: Speed, Signal type, Distance, Node limit, Topology, and Cable type and connectors

Speed: 100 Mbps. Signal type: Baseband. Distance: two kilometers between the hub/switch and the node. Node limit: No more than 1024 nodes per hub/switch. Topology: star-bus topology: physical star, logical bus. Cable type: Multimode fiber-optic cabling with ST or SC connectors

100BaseT Summary: Speed, Signal Type, Distance, Node limit, Topology, and Cable Type:

Speed: 100 Mbps; Signal type: baseband, distance: 100 meters between the hub/switch and teh node. Node limit: no more than 1024 nodes per hub/switch. Topology: star-bus topology: physical star, logical bus. Cable type: Cat 5 or better UTP or STP cabling with RJ-45/8P8C connectors

Two technologies have dropped in price and have replaced PC connectors in some implementations: UPC and APC. Angled Physical Contact (APC) connectors add

an 8-degree angle to the curved end, lowering signal loss further. Plus, their connection does not degrade from multiple insertions, unlike earlier connection types.

1000BaseSX Summary: Connectors

Variable, commonly LC

10GBaseLR/LW: Connectors

Variable, commonly LC

1000BaseLX Summary: Connectors

Variable, commonly LC and SC

10GBaseER/EW: Connectors

Variable, commonly LC and SC

What is the big physical difference between 1000BaseSX and 100BaseFX? 1000BaseSX uses the SC connector exclusively. 1000BaseSX is single-mode, whereas 100BaseFX is multimode. 1000BaseSX uses the ST connector exclusively. There is no difference.

While 1000BaseSX looks similar to 100BaseFX, the former does not allow the use of the ST connector.

Distinguishing a 10BaseT NIC from a 100BaseT NIC without close inspection was __

impossible. You had to look for something on the card to tell you its speed. Some NICs had extra link lights to show the speed (see Chapter 5, "Installing a Physical Network," for the scoop on link lights). Of course, you could always simply install the card, as shown in Figure 4-3, and see what the operating system says it sees.

Standard 10GBaseEW: Fiber Type

single-mode

Standard 10GBaseLR: Fiber type

single-mode

Standard 10GBaseLW: Fiber Type

single-mode

10GBaseER/EW: Cabling

single-mode fiber

10GBaseEy uses an extra-long-wavelength (1550 nm) signal over

single-mode fiber

10GBaseLR/LW: Cabling

single-mode fiber

10GBaseLy uses a long-wavelength (1310 nm) signal over

single-mode fiber.

SFP stands for

small form-factor pluggable

10GBaseER/EW: Wavelength / Cable Details

1550 nm

Standard 10GBaseER: Wavelength

1550 nm

Standard 10GBaseEW: Wavelength

1550 nm

The 10 GbE standards are defined by several factors: the type of fiber used, the wavelength of the laser or lasers, and the Physical layer signaling type. These factors also define the maximum signal distance. The IEEE uses specific letter codes with the standards to help sort out the differences so you know what you're implementing or supporting. All the standards have names in the following format:

"10GBase" followed by two other characters, what I'll call xy. The x stands for the type of fiber (usually, though not officially) and the wavelength of the laser signal; the y stands for the Physical layer signaling standard. The y code is always either R for LAN-based signaling or W for SONET/WAN-based signaling. The x differs a little more, so let's take a look.

Because Ethernet frames don't vary among the many flavors of Ethernet, network hardware manufacturers have long built devices capable of supporting more than one flavor right out of the box. You can also use dedicated media converters to connect any type of Ethernet cabling together. Most media converters are plain-looking boxes with a port or dongle on either side with placement between two segments. They come in all flavors:(4) example

-Single-mode fiber (SMF) to UTP/STP -Multimode fiber (MMF) to UTP/STP -Fiber to coaxial -SMF to MMF

1000BaseT Summary: Length

100 m

100BaseT Summary: Distance

100 meters between the hub/switch and the node

The Ethernet folks are trying to position this as the Ethernet backbone of the future, and already some large carriers are beginning to adopt __

1000BaseLX

_ is the long-distance carrier for Gigabit Ethernet.

1000BaseLX

1000BaseLX connectors look like __ connectors.

1000BaseSX

Many networks upgrading to Gigabit Ethernet use the __ standard.

1000BaseSX

__ devices look similar to 100BaseFX devices, and although both standards can use several types of connectors, __ devices commonly use LC, while 100BaseFX devices frequently use SC

1000BaseSX

The vast majority of network rollouts in offices use a base of __ connections (or drops, as you'll hear them called). You can imagine any number of appropriate scenarios for using __. Many offices also add in wireless today.

1000BaseT

__ is the dominant Gigabit Ethernet standard.

1000BaseT

There is no scenario today where you would install__ networking components, except perhaps to make use of donated equipment. You will definitely find __ gear installed and functioning in many organizations.

100Base

1000BaseSX devices look similar to __ devices, and although both standards can use several types of connectors, 1000BaseSX devices commonly use LC, while __ devices frequently use SC

100BaseFX

UTP cabling cannot meet the needs of every organization for three key reasons. First, the 100-meter distance limitation of UTP-based networks is inadequate for networks covering large buildings or campuses. Second, UTP's lack of electrical shielding makes it a poor choice for networks functioning in locations with high levels of electromagnetic interference (EMI)—disturbance in electrical signals caused by electrical radiation coming from nearby devices. Finally, the Jason Bournes and James Bonds of the world find UTP cabling (and copper cabling in general) easy to tap, making it an inappropriate choice for high-security environments. To address these issues, the IEEE 802.3 standard provides for a flavor of 100-megabit Ethernet using fiber-optic cable, called

100BaseFX

What basically replaced 10BaseFL

100BaseFX

When it came time to come up with a new standard to replace 10BaseT, network hardware makers forwarded a large number of potential standards, all focused on the prize of leading the new Ethernet standard. As a result, two twisted-pair Ethernet standards appeared: 100BaseT4 and 100BaseTX. 100BaseT4 used Cat 3 cable, whereas 100BaseTX used Cat 5 and Cat 5e. By the late 1990s, 100BaseTX became the dominant 100-megabit Ethernet standard. 100BaseT4 disappeared from the market and today has been forgotten. As a result, we never say 100BaseTX, simply choosing to use the term

100BaseT

The CompTIA Network+ exam objectives refer to only five Ethernet standards by name or by category:

100BaseT, 1000BaseT, 1000BaseLX, 1000BaseSX, and 10GBaseT

When it came time to come up with a new standard to replace 10BaseT, network hardware makers forwarded a large number of potential standards, all focused on the prize of leading the new Ethernet standard. As a result, two twisted-pair Ethernet standards appeared:

100BaseT4 and 100BaseTX.

When it came time to come up with a new standard to replace 10BaseT, network hardware makers forwarded a large number of potential standards, all focused on the prize of leading the new Ethernet standard. As a result, two twisted-pair Ethernet standards appeared: 100BaseT4 and 100BaseTX. 100BaseT4 used Cat __ cable, whereas 100BaseTX used Cat __ and Cat __

100BaseT4 used Cat 3 cable, whereas 100BaseTX used Cat 5 and Cat 5e.

100BaseT is another term for

100BaseTX

When it came time to come up with a new standard to replace 10BaseT, network hardware makers forwarded a large number of potential standards, all focused on the prize of leading the new Ethernet standard. As a result, two twisted-pair Ethernet standards appeared: 100BaseT4 and 100BaseTX. 100BaseT4 used Cat 3 cable, whereas 100BaseTX used Cat 5 and Cat 5e. By the late 1990s,__ became the dominant 100-megabit Ethernet standard.

100BaseTX

The 100BaseFX standard saw quite a bit of interest for years, as it combined the high speed of 100-megabit Ethernet with the reliability of fiber optics. Outwardly, 100BaseFX looked exactly like its predecessor, __

10BaseFL

The quest to break 10-Mbps network speeds in Ethernet started in the early 1990s. By then, __ Ethernet had established itself as the most popular networking technology (although other standards, such as IBM's Token Ring, still had some market share).

10BaseT

This chapter looks at the improvements in Ethernet since __.

10BaseT

1000BaseT connections and ports look exactly like the ones on a __ or __ network

10BaseT 100BaseT

__ is the most popular and least expensive 10 GbE media type.

10GBaseLR

10GBaseSy uses a short-wavelength (850 nm) signal over multimode fiber. The maximum fiber length is 300 meters, although this length will vary depending on the type of multimode fiber used. __ is used for Ethernet LANs, and __ is used to connect to SONET devices.

10GBaseSR, 10GBaseSW

It took until 2006 for IEEE to come up with a standard for 10 GbE running on twisted pair cabling—called, predictably,

10GBaseT

It took until 2006 for IEEE to come up with a standard for 10 GbE running on twisted pair cabling—called, predictably, 10GBaseT. 10GBaseT looks and works exactly like the slower versions of UTP Ethernet. The only downside is that

10GBaseT running on Cat 6 has a maximum cable length of only 55 meters. The Cat 6a standard enables 10GBaseT to run at the standard distance of 100 meters.

1000BaseLX is the long-distance carrier for Gigabit Ethernet. 1000BaseLX uses lasers on single-mode cables to shoot data at distances up to __ kilometers—and some manufacturers use special repeaters to increase that to distances as great as 70 kilometers!

5

1000BaseLX Summary: Length

5 km

1000BaseLX Summary: Cable details (wavelength of the light)

1300 nm

10GBaseLR/LW: Wavelength / Cable details

1310 nm

Standard 10GBaseLR: Wavelength

1310 nm

Standard 10GBaseLW: Wavelength

1310 nm

The quest to break 10-Mbps network speeds in Ethernet started in the early (decade).

1990s

10GBaseT: Length

55/100m

Copper-Based 10 GbE It took until __ (year) for IEEE to come up with a standard for 10 GbE running on twisted pair cabling—called, predictably, 10GBaseT

2006

1000BaseSX Summary: Length

220-500 m

Standard: 10GBaseSR: Maximum Signal Length

26 - 300 m

10GBaseSR/SW: Length

26-300 m

Standard: 10GBaseSW: Maximum Signal Length

26-300 m

10GBaseSy uses a short-wavelength (850 nm) signal over multimode fiber. The maximum fiber length is

300 meters, although this length will vary depending on the type of multimode fiber used.

10GBaseEy uses an extra-long-wavelength (1550 nm) signal over single-mode fiber. The maximum fiber length is

40 kilometers, although this length will vary depending on the type of single-mode fiber used.

10GBaseER/EW: Length

40 km

Standard 10GBaseER: Max Signal Length

40 km

Standard 10GBaseEW: Maximum Signal Length

40 km

The IEEE approved two different versions of Gigabit Ethernet. The most widely implemented solution, published under the IEEE 802.3ab standard, is called 1000BaseT. The other version, published under the __ standard and known as __, is divided into a series of standards, with names such as __ and __.

802.3z; 1000BaseX; 1000BaseSX; 1000BaseLX

1000BaseSX uses an __-nm (nanometer) wavelength LED to transmit light on the fiber-optic cable.

850

1000BaseSX Summary: Cable Details (wavelength of the light)

850 nm

10GBaseSR/SW: Wavelength / Cable Details

850 nm

Standard: 10GBaseSR: Wavelength

850 nm

Standard: 10GBaseSW: Wavelength

850 nm

What type of cable and connector does 100BaseFX use? Multimode fiber with ST or SC connectors STP Cat 6 with RJ-45 connectors Single-mode fiber with MT-RJ connectors UTP Cat 5e with RJ-45 connectors

A

Manufacturers have developed technology that relies on wave division multiplexing (WDM) to differentiate wave signals on a single fiber, creating single strand fiber transmission. Bidirectional (BiDi) transceivers (Figure 4-10) have only a single optical port designed inside to send on one wavelength, such as 1310 nm, and receive on a different wavelength, such as 1550 nm. __ for this to work.

A corresponding BiDi transceiver must be installed on the other end of the fiber

What is the maximum cable length of 10GBaseT on Cat 6? 55 meters 100 meters 20 meters 70 meters

A. With Cat 6 cable, 10GBaseT is limited to 55 meters.

APC stands for

Angled Physical Contact (APC)

Two technologies have dropped in price and have replaced PC connectors in some implementations: __ connectors add an 8-degree angle to the curved end, lowering signal loss further. Plus, their connection does not degrade from multiple insertions, unlike earlier connection types.

Angled Physical Contact (APC)

__ connectors add an 8-degree angle to the curved end, lowering signal loss further. Plus, their connection does not degrade from multiple insertions, unlike earlier connection types.

Angled Physical Contact (APC)

Manufacturers have developed technology that relies on wave division multiplexing (WDM) to differentiate wave signals on a single fiber, creating single strand fiber transmission. __ (Figure 4-10) have only a single optical port designed inside to send on one wavelength, such as 1310 nm, and receive on a different wavelength, such as 1550 nm. A corresponding __ must be installed on the other end of the fiber for this to work.

Bidirectional (BiDi) transceivers

With 100BaseT, what is the maximum distance between the hub (or switch) and the node? 1000 meters 400 meters 100 meters 150 meters

C. The maximum distance is 100 meters.

Cat of cable that 100BaseTX used

Cat 5 and Cat 5e

100BaseT Summary: Cable type

Cat 5 or better UTP or STP cabling with RJ-45/8P8C connectors

1000BaseT Summary: Cabling

Cat 5e/6 UTP

10GBaseT: Cabling

Cat 6/6a UTP

10GBaseLy uses a __-wavelength (__ nm) signal over single-mode fiber.

Long; 1310

How many pairs of wires do 10BaseT and 100BaseT use? 4 1 3 2

D

What is the maximum distance for 1000BaseLX without repeaters? 1 mile 2500 meters 20,000 feet 5000 meters

D

How many wire pairs does 1000BaseT use? 1 2 3 4

D. 1000BaseT uses all four pairs of wires.

What is the standard connector for the 10 GbE fiber standard? ST SC MT-RJ There is no standard

D. There is no standard connector; the 10 GbE committee has left this up to the manufacturers.

100BaseFX Summary: Cable type and Connectors

Multimode fiber-optic cabling with ST or SC connectors

By the end of the 1990s, the true speed junkie needed an even more powerful version of Ethernet. In response, the IEEE created

Gigabit Ethernet, which today is the most common type of Ethernet found on new NICs.

10GBaseSy uses a short-wavelength (850 nm) signal over multimode fiber. The maximum fiber length is 300 meters, although this length will vary depending on the type of multimode fiber used. 10GBaseSR is used for

Ethernet LANs

10GBaseEy uses an extra-long-wavelength (1550 nm) signal over single-mode fiber. The maximum fiber length is 40 kilometers, although this length will vary depending on the type of single-mode fiber used. 10GBaseER works with

Ethernet LANs and 10GBaseEW connects to SONET equipment.

10GBaseLy uses a long-wavelength (1310 nm) signal over single-mode fiber. The maximum fiber length is 10 kilometers, although this length will vary depending on the type of single-mode fiber used. 10GBaseLR connects to

Ethernet LANs and 10GBaseLW connects to SONET equipment. 10GBaseLR is the most popular and least expensive 10 GbE media type.

100BaseT was at one time called...

Fast Ethernet. The term still sticks to the 100-Mbps standards even though there are now much faster versions of Ethernet.

Standard 10GBaseLR: Fiber Type / Wavelength / Physical Layer Signaling / Maximum Signal Length

Fiber Type: single-mode. Wavelength: 1310 nm. Physical Layer Signaling: LAN. Maximum Signal Length: 10 km.

Standard 10GBaseLW: Fiber Type / Wavelength / Physical Layer Signaling / Maximum Signal Length

Fiber Type: single-mode. Wavelength: 1310 nm. Physical Layer Signaling: SONET/WAN. Maximum Signal Length: 10 km.

Standard 10GBaseER: Fiber Type / Wavelength / Physical Layer Signaling / Maximum Signal Length

Fiber Type: single-mode. Wavelength: 1550 nm. Physical Layer Signaling: LAN. Maximum Signal Length: 40 km.

Standard 10GBaseEW: Fiber Type / Wavelength / Physical Layer Signaling / Maximum Signal Length

Fiber Type: single-mode. Wavelength: 1550 nm. Physical Layer Signaling: SONET/WAN. Maximum Signal Length: 40 km.

Standard 10GBaseSW: Fiber Type / Wavelength / Physical Layer Signaling / Maximum Signal Length

Fiber type: Multimode . Wavelength 850nm. Physical Layer Signaling: SONET/WAN. Maximum Signal Length: 26-300m

Standard 10GBaseSR: Fiber Type / Wavelength / Physical Layer Signaling / Maximum Signal Length

Fiber type: Multimode. Wavelength 850nm. Physical Layer Signaling: LAN. Maximum Signal Length: 26-300m

BiDi technology has a couple of notable advantages over its dual-fiber predecessors:

First, it costs less to deploy in a new network. You can establish the same level of network performance using half the number of fiber runs. Second, you can use existing fiber runs to rapidly double the capacity of a network. Replace the duplex transceivers with twice the number of BiDi transceivers and plug in the fiber.

UTP cabling cannot meet the needs of every organization for three key reasons.

First, the 100-meter distance limitation of UTP-based networks is inadequate for networks covering large buildings or campuses. Second, UTP's lack of electrical shielding makes it a poor choice for networks functioning in locations with high levels of electromagnetic interference (EMI)—disturbance in electrical signals caused by electrical radiation coming from nearby devices. Finally, the Jason Bournes and James Bonds of the world find UTP cabling (and copper cabling in general) easy to tap, making it an inappropriate choice for high-security environments. To address these issues, the IEEE 802.3 standard provides for a flavor of 100-megabit Ethernet using fiber-optic cable, called 100BaseFX.

When the IEEE members sat down to formalize specifications on Ethernet running at 10 Gbps, they faced an interesting task in several ways:

First, they had to maintain the integrity of the Ethernet frame. Data is king, after all, and the goal was to create a network that could interoperate with any other Ethernet network. Second, they had to figure out how to transfer those frames at such blazing speeds. This second challenge had some interesting ramifications because of two factors. They could use the traditional Physical layer mechanisms defined by the Ethernet standard. But a perfectly usable ~10-Gbps fiber network, called Synchronous Optical Network (SONET), was already in place and being used for wide area networking (WAN) transmissions. What to do?The IEEE created a whole set of 10 GbE standards that could use traditional LAN Physical layer mechanisms, plus a set of standards that could take advantage of the SONET infrastructure and run over the WAN fiber. To make the 10-Gbps jump as easy as possible, the IEEE also recognized the need for different networking situations. Some implementations require data transfers that can run long distances over single-mode fiber, for example, whereas others can make do with short-distance transfers over multimode fiber. This led to a lot of standards for 10 GbE.

Upgrading a 10BaseT network to 100BaseT was not a small process. (3 reasons)

First, you needed Cat 5 cable or better. Second, you had to replace all 10BaseT NICs with 100BaseT NICs. Third, you needed to replace the 10BaseT hub or switch with a 100BaseT hub or switch. Making this upgrade cost a lot in the early days of 100BaseT, so people clamored for a way to make the upgrade a little easier and less expensive. This was accomplished via multispeed, auto-sensing NICs and hubs/switches.

The vast majority of wired networks today feature __ Ethernet, which seems plenty fast for current networking needs.

Gigabit

The term "__" is more commonly used than 1000BaseT.

Gigabit Ethernet

1000BaseT Summary: Cable details

Four-pair /full-duplex

10GBaseT: Wavelength / Cable Details

Four-pair/full-duplex

IEEE standard for 1000BaseT

IEEE 802.3ab

The IEEE approved two different versions of Gigabit Ethernet. The most widely implemented solution, published under the __ standard, is called __

IEEE 802.3ab, 1000BaseT

IEEE standard for 1000BaseX

IEEE 802.3z

Standard 10GBaseER:Physical Layer Signaling

LAN

Standard 10GBaseLR: Physical Layer Signaling

LAN

Standard: 10GBaseSR: Physical Layer Signaling

LAN

You read about the second type of popular SFF connector, the __, in Chapter 2, "Cabling and Topology"—it's shown in Figure 4-7. __-type connectors are very popular, particularly in the United States, and many fiber experts consider the __-type connector to be the predominant fiber connector.

LC

__ and __ are the most popular types of SFF fiber connectors, but many others exist, as outlined in Table 4-1

LC, MT-RJ

1000BaseSX devices look similar to 100BaseFX devices, and although both standards can use several types of connectors, 1000BaseSX devices commonly use __, while 100BaseFX devices frequently use __

LC; SC

This brought about two new types of fiber connectors, known generically as small form factor (SFF) connectors. The first SFF connector—the __ shown in Chapter 2—gained popularity with important companies like Cisco and is still quite common.

Mechanical Transfer Registered Jack (MT-RJ),

Standard: 10GBaseSR: Fiber Type

Multimode

Standard: 10GBaseSW: Fiber Type:

Multimode

1000BaseSX Summary: Cabling

Multimode fiber

10GBaseSR/SW: Cabling

Multimode fiber

100BaseFX Summary: Node limit

No more than 1024 nodes per hub/switch

100BaseT Summary: Node limit

No more than 1024 nodes per hub/switch

Ultra Physical Contact (UPC) connectors are polished extensively for a superior finish. These reduce signal loss significantly over __ connectors.

PC

PC stands for

Physical Contact

Aside from the various connection types (LC, MT-RJ, and so on), fiber connectors vary in the connection point. The standard connector type today is called a __ connector because the two pieces of fiber touch when inserted.

Physical Contact (PC)

Aside from the various connection types (LC, MT-RJ, and so on), fiber connectors vary in the connection point. The standard connector type today is called a

Physical Contact (PC) connector because the two pieces of fiber touch when inserted.

The IEEE uses specific letter codes with the standards to help sort out the differences so you know what you're implementing or supporting. All the standards have names in the following format: "10GBase" followed by two other characters, what I'll call xy. The x stands for the type of fiber (usually, though not officially) and the wavelength of the laser signal; the y stands for the Physical layer signaling standard. The y code is always either

R for LAN-based signaling or W for SONET/WAN-based signaling.

1000BaseT Summary: Connectors

RJ-45

10GBaseT: Connectors

RJ-45

__ connectors snap in and out, making them much more popular than STs. __ connectors are also large, however, and the folks who make fiber networking equipment wanted to pack more connectors onto their boxes.

SC

Gigabit BiDi transceivers typically use __ optics

SFP

Most 10GBase BiDi transceivers use __ connectors.

SFP+

Gigabit BiDi transceivers typically use __ optics. Most 10GBase BiDi transceivers use __+ connectors.

SFP, SFP+

Standard: 10GBaseSW: Physical Layer Signaling

SONET /WAN

10GBaseEy uses an extra-long-wavelength (1550 nm) signal over single-mode fiber. The maximum fiber length is 40 kilometers, although this length will vary depending on the type of single-mode fiber used. 10GBaseER works with Ethernet LANs and 10GBaseEW connects to

SONET equipment

10GBaseLy uses a long-wavelength (1310 nm) signal over single-mode fiber. The maximum fiber length is 10 kilometers, although this length will vary depending on the type of single-mode fiber used. 10GBaseLR connects to Ethernet LANs and 10GBaseLW connects to

SONET equipment. 10GBaseLR is the most popular and least expensive 10 GbE media type.

Standard 10GBaseEW: Physical Layer Signaling

SONET/WAN

Standard 10GBaseLW: Physical Layer Signaling

SONET/WAN

Around the time that Gigabit Ethernet first started to appear, two problems began to surface with ST and SC connectors. First,

ST connectors are relatively large, twist-on connectors, requiring the installer to twist the cable when inserting or removing it. Twisting is not a popular action with fiber-optic cables, as the delicate fibers may fracture. Also, big-fingered techs have a problem with ST connectors if the connectors are too closely packed: they can't get their fingers around them.

The fiber industry has no standard beyond __ and __ connectors, which means that different makers of fiber equipment may have different connections.

ST, SC

1000BaseLX Summary: Cabling

Single-mode fiber

100BaseT Summary: Topology

Star-bus topology: physical star, logical bus

100BaseFX Summary: Topology

Star-bus topology: pnysical star, logical bus

How multisource agreements (MSAs) comes into play with 10 GbE

This hodgepodge of 10 GbE types might have been the ultimate disaster for hardware manufacturers. All types of 10 GbE send and receive the same signal; only the physical medium is different. Imagine a single router that had to come out in seven different versions to match all these types! Instead, the 10 GbE industry simply chose not to define the connector types and devised a very clever, very simple concept called multisource agreements (MSAs): agreements among multiple manufacturers to make interoperable devices and standards. A transceiver based on an MSA plugs into your 10 GbE equipment, enabling you to convert from one media type to another by inserting the right transceiver.

100BaseFX Summary: Distance

Two kilometers between the hub/switch and the node

Two technologies have dropped in price and have replaced PC connectors in some implementations:

UPC and APC. Ultra Physical Contact (UPC) connectors are polished extensively for a superior finish. These reduce signal loss significantly over PC connectors. Angled Physical Contact (APC) connectors add an 8-degree angle to the curved end, lowering signal loss further. Plus, their connection does not degrade from multiple insertions, unlike earlier connection types.

Two technologies have dropped in price and have replaced PC connectors in some implementations: __ connectors are polished extensively for a superior finish.

Ultra Physical Contact (UPC)

UPC stands for

Ultra Physical Contact (UPC)

The beauty and the challenge of the vast selection of Ethernet flavors is deciding which one to use in your network. The goal is to give your users the fastest network response time possible while keeping costs reasonable. To achieve this balance, most network administrators find that a multispeed Ethernet network works best. In a multispeed network,

a series of high-speed (relative to the rest of the network) switches maintain a backbone network. No computers, other than possibly servers, attach directly to this backbone. Figure 4-11 shows a typical backbone network. Each floor has its own switch that connects to every node on the floor. In turn, each of these switches also has a separate high-speed connection to a main switch that resides in the office's computer room.

1000BaseLX is the long-distance carrier for Gigabit Ethernet. 1000BaseLX uses lasers on __ cables to shoot data at distances up to 5 kilometers—and some manufacturers use special repeaters to increase that to distances as great as 70 kilometers!

single-mode

Ethernet networks are (baseband or broadband)?

baseband

The 100BaseFX standard saw quite a bit of interest for years, as it

combined the high speed of 100-megabit Ethernet with the reliability of fiber optics

10GBaseSy uses a short-wavelength (850 nm) signal over multimode fiber. The maximum fiber length is 300 meters, although this length will vary depending on the type of multimode fiber used. 10GBaseSR is used for Ethernet LANs, and 10GBaseSW is used to

connect to SONET devices.

10 GbE has a number of fiber standards and two copper standards. While designed with fiber optics in mind, copper 10 GbE can still often pair excellent performance with

cost savings

The 10 GbE fiber standards do not

define the type of connector to use and instead leave that to manufacturers.

The quest to break 10-Mbps network speeds in Ethernet started in the early 1990s. By then, 10BaseT Ethernet had established itself as the most popular networking technology (although other standards, such as IBM's Token Ring, still had some market share). The goal was to create a new speed standard that made no changes to the actual Ethernet frames themselves. By doing this, the 802.3 committee ensured that

different speeds of Ethernet could interconnect, assuming you had something that could handle the speed differences and a media converter if the connections were different.

Manufacturers have developed technology that relies on wave division multiplexing (WDM) to

differentiate wave signals on a single fiber, creating single strand fiber transmission.

BiDi technology has a couple of notable advantages over its __ predecessors.

dual-fiber

Up to this point, the book has described the most common forms of fiber-optic networking, where fiber is installed in pairs, with one cable to send and the other to receive. This is still the most common fiber-based networking solution out there. All the transceivers used in these technologies have two connectors, a standard __ format.

duplex

10GBaseEy uses an __-wavelength (__ nm) signal over single-mode fiber.

extra-long-wavelength; 1550 nm

Aside from the various connection types (LC, MT-RJ, and so on), fiber connectors vary in the connection point. The standard connector type today is called a Physical Contact (PC) connector because the two pieces of fiber touch when inserted. These connectors replace the older

flat-surface connector that left a little gap between the connection points due to imperfections in the glass.

1000BaseT uses __ cabling to achieve gigabit performance.

four-pair UTP or STP

All NICs today run ...

full-duplex

GBIC stands for

gigabit interface converter

Because Ethernet frames don't vary among the many flavors of Ethernet, network hardware manufacturers have long built devices capable of supporting more than one flavor right out of the box. You can also use dedicated media converters to connect any type of Ethernet cabling together. Most media converters are plain-looking boxes with a port or dongle on either side with placement between two segments. They come in all flavors: Single-mode fiber (SMF) to UTP/STP Multimode fiber (MMF) to UTP/STP Fiber to coaxial SMF to MMF Eventually, the Gigabit Ethernet folks created a standard for modular ports called a

gigabit interface converter (GBIC)..

The beauty and the challenge of the vast selection of Ethernet flavors is deciding which one to use in your network. The goal is to

give your users the fastest network response time possible while keeping costs reasonable.

Ethernet networks are baseband. Contrast this with broadband, where you can get multiple signals to flow over the same wire at the same time, modulating to __ frequencies.

higher

Full-duplex doesn't increase network speed directly, but

it doubles network bandwidth. Imagine a one-lane road expanded to two lanes while keeping the speed limit the same. It also prevents those cars from crashing (colliding) into each other!

1000BaseLX is the long-distance carrier for Gigabit Ethernet. 1000BaseLX uses __ on single-mode cables to shoot data at distances up to 5 kilometers—and some manufacturers use special repeaters to increase that to distances as great as 70 kilometers!

lasers

Aside from the various connection types (LC, MT-RJ, and so on), fiber connectors vary in the connection point. The standard connector type today is called a Physical Contact (PC) connector because the two pieces of fiber touch when inserted. These connectors replace the older flat-surface connector that

left a little gap between the connection points due to imperfections in the glass. PC connectors are highly polished and slightly spherical, reducing the signal loss at the connection point.

Because Ethernet frames don't vary among the many flavors of Ethernet, network hardware manufacturers have...

long built devices capable of supporting more than one flavor right out of the box.

A baseband network means that only a single signal travels over the wires of the network at one time, occupying the __ frequencies.

lowest

The quest to break 10-Mbps network speeds in Ethernet started in the early 1990s. By then, 10BaseT Ethernet had established itself as the most popular networking technology (although other standards, such as IBM's Token Ring, still had some market share). The goal was to create a new speed standard that made no changes to the actual Ethernet frames themselves. By doing this, the 802.3 committee ensured that different speeds of Ethernet could interconnect, assuming you had something that could handle the speed differences and a __ if the connections were different.

media converter

Because Ethernet frames don't vary among the many flavors of Ethernet, network hardware manufacturers have long built devices capable of supporting more than one flavor right out of the box. You can also use dedicated __ to connect any type of Ethernet cabling together.

media converters

Early 100BaseT NICs, just like 10BaseT NICs, could send and receive data, but not at the same time—a feature called half-duplex (Figure 4-4). The IEEE addressed this characteristic shortly after adopting 100BaseT as a standard. By the late 1990s,...

most 100BaseT cards could auto-negotiate for full-duplex. With full-duplex, a NIC can send and receive at the same time, as shown in Figure 4-5.

10GBaseSy uses a short-wavelength (850 nm) signal over __ fiber.

multimode

10GBaseSy uses a short-wavelength (850 nm) signal over...

multimode fiber

Many networks upgrading to Gigabit Ethernet use the 1000BaseSX standard. 1000BaseSX uses__ cabling to connect systems, with a generous maximum cable length of __;

multimode fiber-optic; 220 to 500 meters

100BaseFX uses the __ cabling, and __ connectors

multimode fiber-optic; SC or ST

At the time of this writing, the CompTIA Network+ Acronyms list incorrectly identifies MSA as Master Service Agreement. This chapter uses the correct identification as

multisource agreements

MSAs stands for

multisource agreements

This hodgepodge of 10 GbE types might have been the ultimate disaster for hardware manufacturers. All types of 10 GbE send and receive the same signal; only the physical medium is different. Imagine a single router that had to come out in seven different versions to match all these types! Instead, the 10 GbE industry simply chose not to define the connector types and devised a very clever, very simple concept called

multisource agreements (MSAs): agreements among multiple manufacturers to make interoperable devices and standards. A transceiver based on an MSA plugs into your 10 GbE equipment, enabling you to convert from one media type to another by inserting the right transceiver.

The beauty and the challenge of the vast selection of Ethernet flavors is deciding which one to use in your network. The goal is to give your users the fastest network response time possible while keeping costs reasonable. To achieve this balance, most network administrators find that a __ Ethernet network works best.

multispeed

You'll also have trouble finding a true 10BaseT or 100BaseT NIC any longer because

multispeed NICs have been around long enough to have replaced any single-speed NIC. All modern NICs are multispeed and auto-sensing.

10GBaseLy uses a long-wavelength (1310 nm) signal over __ fiber.

single-mode

Standard 10GBaseER: Fiber Type

single-mode

Upgrading a 10BaseT network to 100BaseT was not a small process. First, you needed Cat 5 cable or better. Second, you had to replace all 10BaseT NICs with 100BaseT NICs. Third, you needed to replace the 10BaseT hub or switch with a 100BaseT hub or switch. Making this upgrade cost a lot in the early days of 100BaseT, so people clamored for a way to make the upgrade a little easier and less expensive. This was accomplished via

multispeed, auto-sensing NICs and hubs/switches.

Manufacturers have developed technology that relies on wave division multiplexing (WDM) to differentiate wave signals on a single fiber, creating single strand fiber transmission. Bidirectional (BiDi) transceivers (Figure 4-10) have only a single optical port designed inside to send on one wavelength, such as 1310 nm, and receive on a different wavelength, such as 1550 nm. A corresponding BiDi transceiver....

must be installed on the other end of the fiber for this to work.

Figure 4-1 shows a typical multispeed, auto-sensing 100BaseT NIC from the late 1990s. When this NIC first connected to a network, it ...

negotiated automatically with the hub or switch to determine the other device's highest speed. If they both did 100BaseT, then you got 100BaseT. If the hub or switch only did 10BaseT, then the NIC did 10BaseT. All of this happened automatically (Figure 4-2).

10GBaseSR/SW: Connectors

not defined

Manufacturers have developed technology that relies on wave division multiplexing (WDM) to differentiate wave signals on a single fiber, creating single strand fiber transmission. Bidirectional (BiDi) transceivers (Figure 4-10) have only

only a single optical port designed inside to send on one wavelength, such as 1310 nm, and receive on a different wavelength, such as 1550 nm. A corresponding BiDi transceiver must be installed on the other end of the fiber for this to work.

A baseband network means that

only a single signal travels over the wires of the network at one time, occupying the lowest frequencies.

Two technologies have dropped in price and have replaced PC connectors in some implementations: UPC and APC. Ultra Physical Contact (UPC) connectors are ...

polished extensively for a superior finish. These reduce signal loss significantly over PC connectors.

PC connectors are highly __ and slightly __, reducing the signal loss at the connection point.

polished; spherical

40GBase BiDi transceivers use __ optics.

quad small form-factor pluggable (QSFP)

10GBaseSy uses a __-wavelength (__ nm) signal over multimode fiber.

short-wavelength; 850nm

Manufacturers have developed technology that relies on wave division multiplexing (WDM) to differentiate wave signals on a single fiber, creating

single strand fiber transmission.

Eventually, the Gigabit Ethernet folks created a standard for modular ports called a gigabit interface converter (GBIC). With many Gigabit Ethernet switches and other hardware, you can simply pull out a GBIC transceiver—the connecting module—that supports one flavor of Gigabit Ethernet and plug in another. You can replace an RJ-45 port GBIC, for example, with an SC GBIC, and it'll work just fine. In this kind of scenario, electronically, the switch or other gigabit device is just that—Gigabit Ethernet—so the physical connections don't matter. Ingenious! Many switches and other network equipment use a much smaller modular transceiver, called a __. Hot-swappable like the GBIC transceivers, the __ take up a lot less space and support all the same networking standards.

small form-factor pluggable (SFP).

Eventually, the Gigabit Ethernet folks created a standard for modular ports called a gigabit interface converter (GBIC). With many Gigabit Ethernet switches and other hardware, you can simply pull out a GBIC transceiver—the connecting module—that supports one flavor of Gigabit Ethernet and plug in another. You can replace an RJ-45 port GBIC, for example, with an SC GBIC, and it'll work just fine. In this kind of scenario, electronically, the switch or other gigabit device is just that—Gigabit Ethernet—so the physical connections don't matter. Ingenious! Many switches and other network equipment use a much smaller modular transceiver, called a

small form-factor pluggable (SFP). Hot-swappable like the GBIC transceivers, the SFPs take up a lot less space and support all the same networking standards.

The 10 GbE standards are defined by several factors: the type of fiber used, the wavelength of the laser or lasers, and the Physical layer signaling type. These factors also define the maximum signal distance. The IEEE uses __ with the standards to help sort out the differences so you know what you're implementing or supporting.

specific letter codes

The beauty and the challenge of the vast selection of Ethernet flavors is deciding which one to use in your network. The goal is to give your users the fastest network response time possible while keeping costs reasonable. To achieve this balance, most network administrators find that a multispeed Ethernet network works best. In a multispeed network, a series of high-speed (relative to the rest of the network) switches maintain a backbone network. No computers, other than possibly servers, attach directly to this backbone. Figure 4-11 shows a typical backbone network. Each floor has its own switch that connects to every node on the floor. In turn, each of these switches also has a separate high-speed connection to a main switch that resides in the office's computer room. To make this work, you need

switches with separate, dedicated, high-speed ports like the ones shown in Figure 4-12. The ports (often fiber) on the switches run straight to the high-speed backbone switch.

This hodgepodge of 10 GbE types might have been the ultimate disaster for hardware manufacturers. All types of 10 GbE send and receive the same signal; only the physical medium is different. Imagine a single router that had to come out in seven different versions to match all these types! Instead,

the 10 GbE industry simply chose not to define the connector types and devised a very clever, very simple concept called multisource agreements (MSAs): agreements among multiple manufacturers to make interoperable devices and standards. A transceiver based on an MSA plugs into your 10 GbE equipment, enabling you to convert from one media type to another by inserting the right transceiver.

The IEEE uses specific letter codes with the standards to help sort out the differences so you know what you're implementing or supporting. All the standards have names in the following format: "10GBase" followed by two other characters, what I'll call xy. the y stands for

the Physical layer signaling standard. The y code is always either R for LAN-based signaling or W for SONET/WAN-based signaling.

The quest to break 10-Mbps network speeds in Ethernet started in the early 1990s. By then, 10BaseT Ethernet had established itself as the most popular networking technology (although other standards, such as IBM's Token Ring, still had some market share). The goal was to create a new speed standard that made no changes to

the actual Ethernet frames themselves. By doing this, the 802.3 committee ensured that different speeds of Ethernet could interconnect, assuming you had something that could handle the speed differences and a media converter if the connections were different.

All NICs today run full-duplex. The NIC and the attached switch determine full- or half-duplex during

the auto-negotiation process.

Aside from the various connection types (LC, MT-RJ, and so on), fiber connectors vary in

the connection point

So, note that when you purchase fiber cables today, you'll see(4):

the connector type and the contact type, plus the type of cable and other physical dimensions. A typical patch cable, for example, would be an SC/UPC single-mode fiber of a specific length.

The wavelength of a particular signal (laser, in this case) refers to

the distance the signal has to travel before it completes its particular shape and starts to repeat. The different colors of the laser signals feature different wavelengths.

This hodgepodge of 10 GbE types might have been the ultimate disaster for hardware manufacturers. All types of 10 GbE send and receive the same signal; only the physical medium is different. Imagine a single router that had to come out in seven different versions to match all these types! Instead, the 10 GbE industry simply chose not to define the connector types and devised a very clever, very simple concept called multisource agreements (MSAs): agreements among multiple manufacturers to make interoperable devices and standards. A transceiver based on an MSA plugs into your 10 GbE equipment, enabling you to convert from one media type to another by inserting the right transceiver. One of the most popular transceivers currently used in 10 GbE is called

the enhanced small form-factor pluggable (SFP+), shown in Figure 4-9.

Two of the defining characteristics of Ethernet—__—stay precisely the same when going from 100-megabit standards to 1000-megabit (and beyond). This standardization ensures communication and scalability.

the frame size and elements, and the way devices share access to the bus (carrier sense multiple access [CSMA])

The 10 GbE standards are defined by several factors: the type of fiber used, the wavelength of the laser or lasers, and the Physical layer signaling type. These factors also define ...

the maximum signal distance.

Aside from the various connection types (LC, MT-RJ, and so on), fiber connectors vary in the connection point. The standard connector type today is called a Physical Contact (PC) connector because the two pieces of fiber touch when inserted. These connectors replace the older flat-surface connector that left a little gap between the connection points due to imperfections in the glass. PC connectors are highly polished and slightly spherical, reducing

the signal loss at the connection point.

It took until 2006 for IEEE to come up with a standard for 10 GbE running on twisted pair cabling—called, predictably, 10GBaseT. 10GBaseT looks and works exactly like

the slower versions of UTP Ethernet. The only downside is that 10GBaseT running on Cat 6 has a maximum cable length of only 55 meters. The Cat 6a standard enables 10GBaseT to run at the standard distance of 100 meters.

Aside from the various connection types (LC, MT-RJ, and so on), fiber connectors vary in the connection point. The standard connector type today is called a Physical Contact (PC) connector because

the two pieces of fiber touch when inserted

The IEEE uses specific letter codes with the standards to help sort out the differences so you know what you're implementing or supporting. All the standards have names in the following format: "10GBase" followed by two other characters, what I'll call xy. The x stands for

the type of fiber (usually, though not officially) and the wavelength of the laser signal; the y stands for the Physical layer signaling standard. The y code is always either R for LAN-based signaling or W for SONET/WAN-based signaling. The x differs a little more, so let's take a look.

The 10 GbE standards are defined by several factors:

the type of fiber used, the wavelength of the laser or lasers, and the Physical layer signaling type. These factors also define the maximum signal distance.

Eventually, the Gigabit Ethernet folks created a standard for modular ports called a gigabit interface converter (GBIC). With many Gigabit Ethernet switches and other hardware, you can simply pull out a GBIC __—the connecting module—that supports one flavor of Gigabit Ethernet and plug in another. You can replace an RJ-45 port GBIC, for example, with an SC GBIC, and it'll work just fine. In this kind of scenario, electronically, the switch or other gigabit device is just that—Gigabit Ethernet—so the physical connections don't matter. Ingenious!

transceiver

10 GbE has a number of fiber standards and __ copper standards.

two

UPC stands for

ultra physical contact

WDM stands for

wave division multiplexing

Manufacturers have developed technology that relies on __ to differentiate wave signals on a single fiber, creating single strand fiber transmission.

wave division multiplexing (WDM)

Manufacturers have developed technology that relies on __ to differentiate wave signals on a single fiber, creating single strand fiber transmission. Bidirectional (BiDi) transceivers (Figure 4-10) have only a single optical port designed inside to send on one wavelength, such as 1310 nm, and receive on a different wavelength, such as 1550 nm. A corresponding BiDi transceiver must be installed on the other end of the fiber for this to work.

wave division multiplexing (WDM)

The __ of a particular signal (laser, in this case) refers to the distance the signal has to travel before it completes its particular shape and starts to repeat. The different colors of the laser signals feature different __(s).

wavelength

A baseband network means that only a single signal travels over the wires of the network at one time, occupying the lowest frequencies. Ethernet networks are baseband. Contrast this with broadband, where

you can get multiple signals to flow over the same wire at the same time, modulating to higher frequencies. The latter is how cable television and cable Internet work.