Private IP address blocks
- 0.0.0/8
- 16.0.0/12
- 168.0.0/16
IPv4 default route
0.0.0.0
Loop back address
127.0.0.0/8
Directs traffic to same host
Link-local addresses
169.254.0.0/16
Can be automatically assigned to clients by OS when no IP configuration is available
Formula to calculate the # of subneta
2 to the n power
Where n = number of bits borrowed
128 in binary
/25
10000000
192 in binary
/26
11000000
224 in binary
/27
11100000
240 in binary
/28
11110000
248 in binary
/29
11111000
252 in binary
/30
11111100
254 in binary
/31
11111110
4 steps to subnetting
1) determine how many bits to borrow based on network requirements
2) determine new subnet mask
3) determine subent multiplier
4) list subnets including subnetwork address, host range, and broadcast address
2 to the 2nd
4
2 to the 3rd
8
2 to the 4th
16
2 to the 5th
32
2 to the 6th
64
2 to the 7th
128
2 to the 8th
256
2 to the 9th
512
2 to the 10th
1024
how to summarize subnet addresses
1) write out networks in binary
2) start w/ left most bit
3) work right and fall all consecutively matching bits
4) when you find a column of bits that do not match, stop. you are at the summary boundary.
5) count # of matching bits, this is subnet mask
6) copy matching bits for summary network address
in IPv6 what analogous to a subnet mask
prefix
-if prefix length is not on quartet boundary write down value for entire quartet
how to abbreviate IPv6 address
- omit leading 0s in any given quartet
- represent 1 or more consecutive quartets of all hex 0s with a double colon (::), but only for one such occurrence
IPv6 address
128 bit
-represented in 8 quartets of 4 hex digits
IPv6 loopback address
::1
IPv4 to IPv6 transition methods
- dual stacking
- tunneling
- NAT-protocol translation
What IPv6 address type is commonly used for establishing neighbor relationships for routing protocols?
Link local address
How to identify a class a address in binary
Always begins with a 0
Range for
0 to 127 in first octet
Network.node.node.node
How to identify a class b address
Always begins with 10 in first octet
Range of 128-191
Network.network.node.node
How to identify class c address
Always begins with 110 in binary
Ranges from 192-223
Network.network.network.node
Private class a address range
10.0.0.0 - 10.255.255.255
Private class b address space
172.16.0.0 - 172.31.255.255
Private class c address space
192.168.0.0 - 192.168.255.255
Easy to determine powers of 2
To find 2 to the 6th you can double 2 to the 5 etc.
/9 mask
255.128.0.0
/10 mask
255.192.0.0
/11 mask
255.224.0.0
/12 mask
255.240.0.0
/13 mask
255.248.0.0
/14 mask
255.252.0.0
/15 mask
255.254.0.0
/16 mask
255.255.0.0
/17 mask
255.255.128.0
/18 mask
255.255.192.0
/19 mask
255.255.224.0
/20
255.255.240.0
/20 mask
255.255.240.0
/21 mask
255.255.248.0
/22 mask
255.255.252.0
/23 mask
255.255.254.0
/24 mask
255.255.255.0
/25 mask
255.255.255.128
1 bit on, 7 off
Block size of 128
2 subnets, each with 126 hosts
/26 mask
255.255.255.192
2 bits on, 6 bits off
Block size 64
4 subnets, each with 62 hosts
/27 mask
255.255.255.224
3 bits on, 5 off
Block size 33
8 subnets with 30 hosts
/28
255.255.255.240
4 bits on 4 off
Block size 16
16 subnets with 14 hosts
/29 mask
255.255.255.248
5 bits on 3 off
Block size 8
32 subnets with 6 hosts
/30 mask
255.255.255.252
6 bits on 2 off
Block size 4
64 subnets with 2 hosts
How to determine number of available subnets
2 to the x power
X=number of masked bits in subnet mask
How many hosts per subnet
2 to the y - 2
Y = number of unmasked bits or 0s in subnet mask
What are the valid subnets?
256 - subnet mask = block size
Start counting from 0 in increments of the block size until you reach subnet mask value
Figure wildcard mask from block size
Subtract one from block size
A block size of 16 would have a wildcard of .15
NAT inside local address
Name of inside source address before translation
NAT outside local address
Name of destination host after translation
NAT inside global address
Name of inside host after translation
NAT outside global address
Name if outside destination host before translation
Command to enable IPv6 on router
Ipv6 uno cast-routing
Command to add ipv6 address to router interface
Ipv6 address / [eui-64]
