Introducing the Topology:
The show controllers command reveals whether the cable is DCE or DTE.
#show controllers serial 0/0/0
Interface serial0/0/0
Hardware is powerQUICC MPC860
DCE v.35, no clock
Interfaces:
By default all Serial and Ethernet interfaces are down.
The routing table will be empty.
Debugging:
Allows us to watch changes a router performs in real time.
For example, to observe routes being added and removed.
#debug ip routing
#undebug all (disables all debug commands). or
#no debug all. or
#un a. (short form)
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Tags: 802.1q, study, vlan, switch, vtp, wan
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IP addressing
By admin 16 July 2008 at 11:53 pm and have Comments Off
IP Addressing Structure:
IPv4 Address = 32 bit # written as dotted decimals
Always paired with a 32 bit mask
Computers evaluate &
E.G. 10101000 <- high-order that side, -> low order this side.
Network = group of hosts with identical network addresses.
Some portion of the low-order bits = host address.
From our 32 bits, the # of bits used in the host portion determines how many hosts we can have in our network.
E.G. if 200 hosts in our network. We need enough bits in the host portion to make 200+ numbers
2^7 = 128, 2^8 = 256, therefore 8 bits minimum are required to get 200+ hosts.
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Tags: vlan, cisco, switch, ip, router, wan