Security

A downloadable ACL is another from of Port ACL that can be assigned dynamically by a RADIUS authentication server such as Cisco ISE. After successful network authentication, if a PACL is configured on the switchport and a dACL is assigned by the authoritative server, the PACL will be overwritten by the dACL.

If a PACL, VACL, and RACL (Router ACL) are all configured in the same VLAN. The ACLs are evaluated in a certain order. Bridged Traffic Inbound PACL on the switchport Inbound VACL on the VLAN Outbound VACL on the VLAN Routed Traffic Inbound PACL on the switchport Inbound VACL on the VLAN Inbound ACL on…

A VACL can filter traffic bridged within a VLAN or routed in and out of a VLAN. ! Block ICMP ip access-list extended ICMP deny icmp any any ! Forward everything else ip access-list extended OTHER permit ip any any ! Construct the access map vlan access-map VACL_10 10 match ip address ICMP action drop…

The syntax for configuring a Port Access Control List is the same as creating any other access control list. The difference is Port Access Control lists support filtering via MAC address via a different CLI syntax. PACLs can only support filtering of incoming traffic with no outbound filtering support. PACLs can not filter control packets…

Named access control lists allow for easier identification of an access control lists purpose if a suitable naming convention is followed. They function in the same way as standard and extended access control lists – they just have a different method of being created. ip access-list standard restrict_vty permit host 192.168.10.20 permit host 10.55.55.20 deny…

The process for defining an extended access control list: access-list 2100 permit ip 192.168.1.0 0.0.0.255 192.168.2.0 0.0.0.255 The above configuration will permit access from 192.168.1.0/24 to 192.168.2.0/24 An extended numbered access list can have a number between 100 to 199 or 2300 to 2699 Some additional flexibility is present with extended access control lists. Greater…

The process for defining a numbered standard access control list for the network 192.168.1.0 to be permitted and the 192.168.2.0 to be denied and logged: access-list 10 permit 192.168.1.0 0.0.0.255 access-list 10 deny 192.168.2.0 0.0.0.255 log The access-control list is applied to the inteface interface GigabitEthernet0/0 ip access-group 10 in Note the standard access control…

An access control list is an sequential list of access control entries that can perform or deny packets based on inputted matching statements. The classification begins at the lowest sequence number, and works its way down through the larger sequence numbers until a matching pattern has been found for the packet being analysed. When a…

MACsec is an IEEE 802.1AE standards based Layer 2 hop-by-hop encryption method. Traffic is encrypted on the wire between two MACsec peers and is unencrypted to process internally on the switch. It allows the switch to look for objects inside of the packet such as SGT enforcement or Quality of Service priortisation. MACsec can utilise…

TrustSec is the next generation access-control enforcement solution developed by Cisco to address growing operational challenges regarding firewall rules and access control lists. TrustSec uses Scalable Group Tags to perform ingress tagging and egress filtering to enforce access control policy. Cisco ISE assigns Scaleable Group Tags to users or devices that have authenticated and are…