Standard Access Control lists are a list of conditions that are used in the network to avoid traffic. The conditions are listed in numbers or names. And these conditions are used to avoid traffic on routes. Through these conditions, we can avoid or filter traffic. When an interface receives a packet following procedures happens:
- The first router grasps the destination address of the packet.
- Secondly, the routing table contains the address and these are used to check the address of the destination.
- Thirdly, the interface forward the address only the above comparisons are get matched.
- The match is not found the packet will get discarded.
There are three different types of ACLs, they are:
- Standard ACLs
- Extended ACLs
- Named ACLs
Standard ACLs (1-99 and 1300-1999) simpler filtering at the beginning of filtering.so standard ACLs are used only for simple filtering. Based on the source address of the packet the filtering of traffic takes place.
Extended ACLs (100-199 and 2000-2699) when the occurrence of traffic increases the time required for filtering is not sufficient, so it becomes s challenging task. To minimize the time security advanced filtering requires.so for that Extended ACLs were used.
Standard Access Control List is a type of access control list used to filter the traffic and is not commonly used one is an odd one. The traffics is controlled along with the data contained with them. The traffics in the networks is controlled based on the source IP addresses. By using the “access-list” IOS command standard access list can be created.
Characteristics of Standard Access Control lists are pointed below:
To write the standard access control lists ACL numbers are used. The range of the number used is from 1-99. So any number between 1 and 99 is the standard access control list.
Network traffics are removed based on the source IP addresses. In other words, we can say that ACL rules are stated based on the source addresses.
The main source of the ACL mentioned is based on the source IP address. So the filtration happens at the place close to the destination.
The outbound direction is the important and best place we can apply to the SAC list.
To identify the devices or the address of the packet we can use the wildcard mask for a SAC list or an extended access control list.
TO PLACE STANDARD ACCESS CONTROL LIST
Traffic filtration of network processing based on the source IP addresses in the router SAC lists are placed. Near the destination network, there is a router in which the SAC list was placed. If it is not kept near to the destination there will be traffic problems occur during the process.
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