CHAPTER 2. Packet Filtering230 © SAMSUNG Electronics Co., Ltd.MAC filtering is supported on inbound packets only. MAC filtering can beapplied to:y Source MAC and source mask addressesy Destination MAC and destination mask addressesy Ethernet typey Class of Service(CoS)y VLAN IDExample: Blocking Telnet AccessConsider a Ubigate iBG2016 connected via a bundle ‘WAN1’(wan IP address200.1.1.1) to an ISP, with Ethernet 0/1(IP address 222.199.19.3) connected tothe internal network. The network administrator wants to completely blockTelnet access to the Ubigate iBG2016 from all external networks as well asfrom all internal networks except 222.199.19.0/28. All other TCP/IP traffic,such as FTP, Ping, and HTTP, is to flow unrestricted through the UbigateiBG2016.Configure the Ubigate iBG2016Router# configure termRouter/configure# ip access-list filteraRouter/configure/ip/access-list filtera# add deny tcp any200.1.1.1 dport =23Router/configure/ip/access-list# add permit tcp222.199.19.0/28 222.199.19.3 dport =23Router/configure/ip/access-list# add deny tcp any222.199.19.3 dport=23Router/configure/ip/access-list# add permit ip any anyRouter/configure/ip/access-list# endRouter# save local
