Cuckoo - collect resources on other proxy's cache

Cuckoo is catalyst mode of Wcol.

When you want prfeteching proxy server, you can select 2 ways for it.

  1. Use wcol by proxy server mode.
  2. Use wcol by catalyst mode with some proxy(ies).
This page describe catalyst mode of Wcol.

What is Cuckoo ? Catalyst ?

Today, proxy server is very important to site management. Installation of new proxy is should be very carefully. Catalyst mode of wcol makes prefetching proxy server withoout replacement of proxy server. You can prfetching proxy server via little cost.

In catalyst mode, wcol get resources from original server via other proxy. And resources stored that proxy. Wcol is prefetching system for WWW. So, that proxy store prefetching result s by wcol. 


        +------+  HTTP  +------+  HTTP  +------+
        |server|<-------|proxy |<-------|client|
        +------+        +------+        +------+
                           |\ HTTP
                           |    (prefetch)
                        +------+
                        | wcol |
                        +------+

How to prefetch ?

Modern WWW proxy servers support ICP (Internet Cache Protocol). They exchange resources via ICP. Wcol get client's request by proxy's ICP request. Wcol send request that resources and linked some resources. 


        +------+  HTTP  +------+  HTTP  +------+
        |server|<-------|proxy |<-------|client|
        +------+        +------+        +------+
                          |  |\ HTTP
                     ICP \|  |
                        +------+
                        | wcol |
                        +------+

Configuration example

This example shows wcol in catalyst mode and squid.

2 hosts

If you have two hosts, easy to setup. 

        +------+  HTTP  +------+  HTTP  +------+
        |server|<-------|proxy |<-------|client|
        +------+        +------+7000    +------+
                          | 7000
                          |  |\ HTTP
                     ICP \|  |
                       3130  |
                        +------+
                        | wcol |
                        +------+
squid configuraion: http_port 7000 cache_host wcol.foo.com neighbor 9000 3130 wcol configuration: Catalyst NextProxy http://squid.foo.com:7000/ HTTPPort 9000

1 host

Squid use ICP port 3130. Then, change ICP port of wcol to others (e.g. 3131). 

                    /---------------\
                    |               |
        +------+  HTTP  +------+   HTTP +------+
        |server|<-------|proxy |<-------|client|
        +------+    |   +------+7000|   +------+
                    |     | 7000    |
                    |     |  |\ HTTP|
                    |ICP \|  |      |
                    |  3131  |      |
                    |   +------+    |
                    |   | wcol |    |
                    |   +------+    |
                    |               |
                    \---------------/
squid configuraion: http_port 7000 cache_host wcol.foo.com neighbor 9000 3131 wcol configuration: Catalyst NextProxy http://squid.foo.com:7000/ HTTPPort 9000 ICPPort 3131
k-chinen@is.aist-nara.ac.jp , 1996