Hi All,
I got myself lately Cisco SR520 router with some basic firewall functions built in. This is going to be used for my home broadband, so no need to be really super secure, as it would be for some business. I managed to configure it, however there are few things on the firewall side, which I dont understand.
This router had some default configuraton in it's flash, when I bought it. There are class maps.... I have no idea how it works or how to add/edit rules. Also, do I need to use class maps, or can they be replaced by ACL's to certain extend? If somebody could explain me how to add/edit class maps rules to allow certain port (eg. 3333), that would be great. Please see below part of the default config:
!
class-map type inspect match-any SDM-Voice-permit
match protocol sip
class-map type inspect match-any sdm-cls-icmp-access
match protocol icmp
match protocol tcp
match protocol udp
class-map type inspect match-any sdm-cls-insp-traffic
match protocol cuseeme
match protocol dns
match protocol ftp
match protocol h323
match protocol https
match protocol icmp
match protocol imap
match protocol pop3
match protocol netshow
match protocol shell
match protocol realmedia
match protocol rtsp
match protocol smtp extended
match protocol sql-net
match protocol streamworks
match protocol tftp
match protocol vdolive
match protocol tcp
match protocol udp
class-map type inspect match-all sdm-invalid-src
match access-group 100
class-map type inspect match-all dhcp_out_self
match access-group name dhcp-resp-permit
class-map type inspect match-all dhcp_self_out
match access-group name dhcp-req-permit
class-map type inspect match-all sdm-protocol-http
match protocol http
!
!
policy-map type inspect sdm-permit-icmpreply
class type inspect dhcp_self_out
pass
class type inspect sdm-cls-icmp-access
inspect
class class-default
pass
policy-map type inspect sdm-inspect
class type inspect sdm-invalid-src
drop log
class type inspect sdm-cls-insp-traffic
inspect
class type inspect sdm-protocol-http
inspect
class type inspect SDM-Voice-permit
pass
class class-default
pass
policy-map type inspect sdm-inspect-voip-in
class type inspect SDM-Voice-permit
pass
class class-default
drop
policy-map type inspect sdm-permit
class type inspect dhcp_out_self
pass
class class-default
drop
!
zone security out-zone
zone security in-zone
zone-pair security sdm-zp-self-out source self destination out-zone
service-policy type inspect sdm-permit-icmpreply
zone-pair security sdm-zp-out-self source out-zone destination self
service-policy type inspect sdm-permit
zone-pair security sdm-zp-in-out source in-zone destination out-zone
service-policy type inspect sdm-inspect
zone-pair security sdm-zp-out-in source out-zone destination in-zone
service-policy type inspect sdm-inspect-voip-in
!
Thank you in advance
