RIP: Triggered RIP (demand circuit) documentation

diff --git a/doc/bird.sgml b/doc/bird.sgml
index 786f124b7f105e8e074ce85a4449c2c96691cb88..33f6418f5f4775278309cbc40d111ee96953e40f 100644 (file)
--- a/doc/bird.sgml
+++ b/doc/bird.sgml
@@ -4443,7 +4443,8 @@ you can't use RIP on networks where maximal distance is higher than 15
 hosts.
 
 <p>BIRD supports RIPv1 (<rfc id="1058">), RIPv2 (<rfc id="2453">), RIPng (<rfc
-id="2080">), and RIP cryptographic authentication (<rfc id="4822">).
+id="2080">), Triggered RIP for demand circuits (<rfc id="2091">), and RIP
+cryptographic authentication (<rfc id="4822">).
 
 <p>RIP is a very simple protocol, and it has a lot of shortcomings. Slow
 convergence, big network load and inability to handle larger networks makes it
@@ -4473,6 +4474,7 @@ protocol rip [ng] [&lt;name&gt;] {
                version 1|2;
                split horizon &lt;switch&gt;;
                poison reverse &lt;switch&gt;;
+               demand circuit &lt;switch&gt;;
                check zero &lt;switch&gt;;
                update time &lt;number&gt;;
                timeout time &lt;number&gt;;
@@ -4577,6 +4579,16 @@ protocol rip [ng] [&lt;name&gt;] {
        used. The poisoned reverse has some advantages in faster convergence,
        but uses more network traffic. Default: yes.
 
+       <tag><label id="rip-iface-demand-circuit">demand circuit <m/switch/</tag>
+       Regular RIP sends periodic full updates on an interface. There is the
+       Triggered RIP extension for demand circuits (<rfc id="2091">), which
+       removes periodic updates and introduces update acknowledgments. When
+       enabled, there is no RIP communication in steady-state network. Note
+       that in order to work, it must be enabled on both sides. As there are
+       no hello packets, it depends on hardware link state to detect neighbor
+       failures. Also, it is designed for PtP links and it does not work
+       properly with multiple RIP neighbors on an interface. Default: no.
+
        <tag><label id="rip-iface-check-zero">check zero <m/switch/</tag>
        Received RIPv1 packets with non-zero values in reserved fields should
        be discarded. This option specifies whether the check is performed or

diff --git a/proto/rip/rip.c b/proto/rip/rip.c
index d18ff5adfab6e06b09cf85e5aa5686f83a7d99ec..f3dc63535d6471c184c08d000d07d1580aa991cb 100644 (file)
--- a/proto/rip/rip.c
+++ b/proto/rip/rip.c
@@ -69,10 +69,11 @@
  * structure is finally freed.
  *
  * Supported standards:
- * - RFC 1058 - RIPv1
- * - RFC 2453 - RIPv2
- * - RFC 2080 - RIPng
- * - RFC 4822 - RIP cryptographic authentication
+ * RFC 1058 - RIPv1
+ * RFC 2453 - RIPv2
+ * RFC 2080 - RIPng
+ * RFC 2091 - Triggered RIP for demand circuits
+ * RFC 4822 - RIP cryptographic authentication
  */
 
 #include <stdlib.h>