5
Configuring Interfaces
102
Voyager Reference Guide
lists, packets which establish and maintain a connection will be termed
“interesting.”
A DDR list is comprised of one or more rules that are used to determine if a
packet is “interesting.” Each rule has a set of values used for matching a
packet and an action to take to take on a match.
There are three possible actions:
!
Accept—This is an interesting packet.
!
Ignore—This is not an interesting packet.
!
Skip—This rule is ignored.
When a packet matches a rule in the DDR list with an “accept” action, that
packet is regarded as being “interesting.” An “interesting” packet will cause
the ISDN interface to set up a call using the configured connection
information for the interface. When the connection is established, traffic will
be passed over the interface. The traffic passed could include traffic, which
configured in the DDR list, with an “ignore” action. If no packets that match
an “accept” rule in the DDR list are transmitted in the configured idle time,
the connection is automatically disconnected. A DDR list is created with a
default rule that matches all packets. The associated action is “accept.” This
action can be set to “skip” so that all unmatched packets are deemed
“uninteresting.”
Note
Setting a rule to “skip” effectively turns the rule off.
It is important to understand the difference between Access lists and DDR
lists and how the two interoperate. When a packet is sent over an interface,
any Access list applied to that interface is checked first. If the packet matches
any rule in the Access list, the associated action will be taken. Therefore, if
the packet matched a rule in the Access list that had an associated action of
drop, the packet will never be sent over the ISDN interface. After the packet is
checked against the Access list, the DDR list applied to the interface (if any)
is then checked.
Summary of Contents for Network Voyager
Page 1: ...Voyager Reference Guide Part No N450820002 Rev A Published December 2003 ...
Page 4: ...4 Voyager Reference Guide ...
Page 30: ...2 How to Use Voyager 30 Voyager Reference Guide ...
Page 32: ...3 Command Line Utility Files 32 Voyager Reference Guide ...
Page 220: ...5 Configuring Interfaces 220 Voyager Reference Guide ...
Page 446: ...7 Configuring Traffic Management 448 Voyager Reference Guide ...
Page 618: ...10 Configuring Security and Access 620 Voyager Reference Guide ...
Page 668: ...14 Configuring IPv6 670 Voyager Reference Guide ...
Page 672: ...15 IPSO Process Management 674 Voyager Reference Guide ...
Page 700: ...Index 702 Voyager Reference Guide ...
