TCP/IP

Which of the following is not a "special" IP address?

169.253.4.185 is a valid class B address (note, any address that starts with 169.245 is an Automatic Private IP Address - APIPA). Watch for this subtle type of distinction on the CompTIA exam.

Which feature of a SOHO router is not typically found in an enterprise router?

Built-in switch Very few enterprise routers have a built-in switch.

Here are three IP addresses: 216.53.12.11, 130.222.255.170, 223.255.6.88. What class of addresses are each one (in order)?

C, B, C The first octet of a Class A address goes from 1 to 126. The first octet of a Class B address goes from 128 to 191. The first octet of a Class C address goes from 192 to 223.

A tech has just installed a new SOHO router for a client. Which security task should the tech perform first?

Change the administrator name and password. The default admin name and password of all makes and models are well known. It is critical to change these right away to prevent the router from being hacked.

Which of the following is a not an element of a route metric?

Hop distance The physical distance between to routers is not considered when defining a metric.

Which statement is true of a NAT router?

NAT routers replace the source IP address with its own IP address. NAT routers replace the source IP address with its own IP address and then restore the original IP header when a response comes back so that the results can be sent to the originator.

Which of the following is not a characteristic of the OSPF routing protocol?

OSPF is a distance vector protocol. Open Shortest Path First (OSPF) is not a distance vector protocol, it is a link state protocol.

Which of the following is not a characteristic of the BGP routing protocol?

OSPF is the primary routing protocol between Ases. Border Gateway Protocol (BGP) uses OSPF (and other routing protocols) within autonomous systems but not between different ASes.

Port forwarding allows which of the following?

Outside access to hosts on the LAN side of a NAT router Port forwarding enables access to hosts on the LAN side of a NAT router from beyond the WAN interface of the router.

What is the role of port numbers in IP headers?

Port numbers identify the sending and receiving processes between two hosts

Which service does not automatically assign an IP address to a host?

Static Static IP addressing sets a constant, unchanging IP address to a host.

Which symptom is not a result of an IP addressing problem?

Static IP address There is nothing wrong with assigning static IP addresses so long as the rules of assigning addresses are followed.

Which statement is not true of static routes?

Static routes are entered manually but can be automatically changed by the router. Static routes must be manually entered by a human and, once entered, cannot be automatically changed by a router. When a router automatically changes a route, this is called dynamic routing and is the opposite of static routing.

Which statement is not true of a subnet mask?

Subnet masks are sent out as one of the fields in the IP packet.

An organization wants each of five buildings to be on its own subnet. Each campus will need a minimum of 25 IP addresses. The organization has the Class C network address 217.105. 2.0 assigned to it. Using CIDR, what subnet mask will the minimum number of subnetworks with the maximum number of hosts per network that will meet the requirements of the organization?

/27 /27 will result in 6 subnetworks with 30 hosts per subnet.

A company has subnetted their Class C network address into four subnets with a /26 subnet mask. What are the addresses of the four subnets?

0, 64, 128, and 192 represent all of the possible values of 1s and 0s in the first two columns of the fourth octet in a Class C address: 0 0, 0 1, 1 0, and 1 1. Place those values under a 128 and a 64 and calculate the results.

Which of the following is not a characteristic of the RIP routing protocol?

RIP supports a maximum hop count of 127 hops. Router Information Protocol (RIP) supports a maximum hop count of 15 hops, not 127 hops.

Which choice is true of a rogue DHCP server?

Rogue DHCP servers can assign incompatible IP addresses to hosts on a network, making them unable to communicate with other hosts or the Internet.

Most SOHO routers come with NAT enabled.

TRUE Most SOHO routers come with NAT enabled. It can be disabled and/or enabled in one of the router's administration settings.

What is the job of a router?

The job of a router is to connect networks with different network IDs .