NETWORKING INTERVIEW QUESTIONS

What are the major classes of IP network
A,B,C,D,E

• What is a Class D IP address?
Multicast Addresses

• What addresses do multicast start with?
224.0.0.0

• What is OSPF?
Open Shortest Path First. A routing protocol which supports the concept of a "core" area to which everything attatchs. Enforces a structure to the routed network.

• What is BPF?
Border Gateway Protocol. Currently version 4. BGP is used for routing between networks on the Internet core, it supports many advanced routing features.

• Define an autonomous system?
An autonomous system is a community of interest. Used in conjuction with routing protocols, it breaks up parts of the network into manageable chunks.

• What does the Ether type code do?
It differentiates which protocol is being carried by the ethernet frame.

• How would you configure a three router network with an Internet connection?
Default routes, ip classless, ISDN or Frame Relay, no wrong answers.

• What is "dial on demand"?
Dial on demand is a "technology" which only activates network connection when "interesting" packets are to be sent across the infrastructure.

• How many bytes in an IPX network address?
An IPX address is made up of 4 bytes of Network address and 6 bytes of node address and takes the form of ABABABAB.FFFF.FFFF.FFFF. The address is in hexidecimal. The network address is allocated by the network (usually the servers or routers) and the node address is the MAC address of the device.

• What mask would you use to supernet two class C addresses?
255.255.254.0, the first address must be even, ie 203.14.2.0 with the mask of 255.255.254.0 makes a network of 203.14.2.0 - 203.14.2.255.

• What is LANE?
LAN Emulation used to run normal networking over ATM, it emulates the broadcast nature of a LAN over connection oriented ATM.

• What is CIDR?
Classless Internet Domain Routing, used in conjuction with Classless routing protocols to summarise the internet into smaller routing tables.

• What is VLSM?
Variable Length Subnet Mask, used to allocate the amount of address space required by the end network.