Which statement about extended access lists is true?

Which statement about extended access lists is true?
A . Extended access lists perform filtering that is based on source and destination and are most effective when applied to the destination
B . Extended access lists perform filtering that is based on source and destination and are most effective when applied to the source
C . Extended access lists perform filtering that is based on destination and are most effective when applied to the source
D . Extended access lists perform filtering that is based on source and are most effective when applied to the destination

View Answer

Answer: B

Explanation:

Source: http://www.ciscopress.com/articles/article.asp?p=1697887

Standard ACL

1) Able Restrict, deny & filter packets by Host Ip or subnet only.

2) Best Practice is put Std. ACL restriction near from Source Host/Subnet (Interface-In-bound).

3) No Protocol based restriction. (Only HOST IP).

Extended ACL

1) More flexible then Standard ACL.

2) You can filter packets by Host/Subnet as well as Protocol/TCPPort/UDPPort.

3) Best Practice is put restriction near form Destination Host/Subnet. (Interface-Outbound)