Chapter 8: TCP/IP Inter-networking I

A mask always begins with _____'s then _____'s.

1, 0

In the mask 255.255.255.0, how many 1s are there?

24

A mask has _______ bits.

32

The network part ranges from _______ bits to _______ bits.

8 and 24

What is the Routing Table?

A routing table has rows of IP addresses that a frame can be forwarded to, not just a single address.

What are the reasons to use the User Datagram Protocol (UDP) instead of using the Transmission Protocol (TCP)?

Because User Datagram Protocol produces substantially less traffic since it does not use openings, closings, or acknowledgements.

_______ main job is to connect different networks.

Border Router

You _______ determine which bit correspond to the network, subnet, and host parts.

Can not

TCP/IP has many supervisory standards at the internet and application layers:

DNS, Dynamic Routing Protocols, and many others

What is the row number column in the routing table?

Designates the row in the routing table

What is the TCP Sequence Number?

Each message is given a sequence number. This allows the receiver to ensure that no message is missing and to deal with duplicate segments.

_______ are organized in a hierarchy, so there is only one possible port to send a frame out and so only one row per EUI-48 address.

Ethernet switches Finding this one matching row is very fast. So switches are inexpensive per frame handled.

There is a row for each individual Ethernet address in a(n) _______.

Ethernet switching table

A TCP _______ segment is a request to close a connection.

FIN

The Application layer holds what protocols?

HTTP, SMTP, DNS, Dynamic Routing Protocols, etc.

TCP/IP has many application standards:

HTTP, SMTP, and many others These standards govern how application communication work between hosts

The _______ specifies a particular host on the subnet.

Host part

The Internet layer holds what protocols?

IP, ICMP, and ARP

TCP/IP has core internet and transport standards:

IP, TCP, and UDP

What is Ethernet Switching, the process?

Indicate a specific device address that the frame should be forwarded to.

Router ports are called _______.

Interfaces

An _______ only connects different subnets within a network.

Internal router

Internets operate at _______ and _______.

Internet and transport layer *Standards come predominantly from the Internet Engineering Task Force (IETF) *Called TCP/IP standards *Publications are Requests for Comments (RFCs)

What does a router do with Address Resolution Protocol request messages?

It broadcasts them

What is the TCP Acknowledgement number?

It indicates which segment is being acknowledged.

The network part of an IPv4 address is _______ bits long.

It is hard to say with limited information

_______ identifies the host's network on the Internet.

Network part

Single switched and wireless networks operate at _______ and _______.

Physical and data link layers *standards come almost entirely from OSI

In _______, a mask is represented by a slash followed by the number of initial 1s in the mask.

Prefix notation

An abrupt close uses a(n) _______ segment.

RST

What is the destination column in the routing table?

Range of IP addresses governed by the row.

The host part comes after the Network and Subnet part, the length of the host part is the ________.

Remaining bits in the IP address.

What is the purpose of the Address Resolution Protocol (ARP)?

Routers use ARP to find the DLL destination addresses (MAC/EUI-48 Address) of both destination hosts and other routers.

What is, processing an individual packet and passing it closer to its destination host?

Routing

When a router forwards incoming packets closer to their destination hosts, this is _______.

Routing

When routers forward incoming packets closer to their destination hosts, this is called _______.

Routing

What is the purpose of the IPv4 Source address field?

So the destination knows which address to send responses or error messages back to.

What is the purpose of the IPv4 Destination address field?

So the sender knows where to send the packet.

_______ bits specify a particular subnet within the network.

Subnet part

The Transport layer holds what protocols?

TCP and UDP

How does the Transmission Control Protocol work?

TCP applies sequence numbers to segments, which allows it to fragment long application messages and deliver the segments with an indication of their order.

The Physical and Data Link Layers hold what protocols?

The OSI Standards

The main benefit of IPv6 over IPv4 is _______.

The ability to support more possible hosts

What is the TCP/UDP data field?

The data field contains the content being delivered by the message.

What is the TCP/UDP Destination port?

The destination port specifies the receiver's port number.

What is the Next-Hope Router column in the routing table?

The device (router or destination host) on the interface subnet to receive the packet.

What is the format of IPv6?

The format of IPv6 is 128 bits, in hexadecimal, separated by colons. Example: 1A21:3D32:12F2:123F:14FF:4132:0000:0000

What is the Interface column in the routing table?

The interface (port) to use to send the packet out.

What is the Mask column in the routing table?

The mask for the row.

What is the purpose of the Network Masks?

The network mask is to allocate the portion of the IP address as the Network part

What is Simple Network Management Protocol (SNMP)?

The protocol that allows a general way to collect rich data from various managed devices in a network.

What is the purpose of the IPv4 field Time to Live (TTL)?

The purpose of Time to Live is to make sure that packets do not circulate endlessly among packets switches in search of their nonexistent destinations.

What is the purpose of the IPv4 Protocol Field?

The purpose of the Protocol Field is to tell the destination host the contents of the data field.

What is the Metric column in the routing table?

The quality of the route listed in this row.

What are the reasons for moving from IPv4 to IPv6?

The reason for the switch was due to impending address exhaustion, with various other goals: Support billions of hosts Simplify protocol Better security ETC.

What is the TCP/UDP Source port?

The source port specifies the sender's port number.

What is the purpose of the Subnet Masks?

The subnet masks is to allocate the portion of the IP address as the Subnet part.

How does Use Datagram Protocol work?

There is a UDP length field to allow the receiving transport process to know how long the data gram is. There is a UDP checksum field that allows the receiver to check for errors in the datagram, if there are errors however, it is discarded.

What is meant by hierarchical IP addresses?

They usually consist of three parts that locate a host in progressively smaller parts of the Internet. The parts include the network, subnet, and host parts.

Subnet lengths ______.

Vary widely

How is the Transmission Control Protocol reliable?

What makes TCP reliable is that when there is an error on the receiving end, the receiver does not send an ACK so the sender re-sends the damaged fragment.

What is the Routing Process?

Whenever a packet arrives, the router looks at its destination IP address, then... Finds all Row matches, Finds the Best-Math Row, Then sends the packet Back out according to Direction in the Best-Match Row.

For human reading, IPv6 fields are separated by ________.

colons

The tool that allows routers to tell the sizes of network, subnet, and host parts is a _______.

mask

A _______ is a string of _______, like an IP address.

mask, 32 bits

In _______, the initial 1s correspond to the network part.

network masks

A _______ may send a packet out more than one interface (port) and still get the packet to its destination host.

router More than expensive than switches because it is more complex

In _______, the initial 1s correspond to the network and subnet parts.

subnet masks