Planet Technology ERT-805 Chapter 5 Security, 5.1 Access-list, Standard, Extended, [in | out], access-list, access-list, Access-list, access-lists, access-group, [permit | deny]

Chapter 5 Security

5.1 Access-list

The purpose for access-list is packet filtering to control, which packets move through the network. Such control can help limit network traffic and restrict network use by certain user or device.

Access-list is use as a packet filter, this function helps to limit network traffic and restrict network.

There are two general types of access lists:

ØStandard access-lists– The standard access-list is check the source address of packets. Access-list number is start from 1-99

ØExtended access-list– The extended access-list is check for both source and destination packet address and also check for specific protocols, port numbers and other parameters. Access-list number is start from 100-199

access-listaccess-list number [permit deny] – set the standard access-list’s rule.

ip access-group [in out] – applies an existing access-list as an incoming or outgoing to an interface.

Access-listaccess-list number [permit deny] protocol source-address source-wildcard destination-address destination-wildcard [operator port] – set the extended access-list rule.

Standard access-list configuration example

ERT-805# show run

Building configuration ...

service password-encryption service timestamps debug

!

hostname ERT-805

!

enable password 7 5EVbxkwzBvfT

!

username router password 7 qBjbURagjK0L

!

interface fastethernet 0/0

ip address 192.168.98.63 255.255.255.0

!

interface serial 0/0 encapsulation ppp

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