4 Protocol Examples
GET /index.html HTTP/1.1 Host: www.hostname.com Accept: */* Accept-Language: en-US Accept-Encoding: gzip, deflate, peerdist X-P2P-PeerDist: Version=1.1 X-P2P-PeerDistEx: MinContentInformation=1.0, MaxContentInformation=1.0 User-Agent: Mozilla/4.0
In this example, the HTTP client announces that it is ready to accept the response entity-body that is encoded using the PeerDist content encoding. It also declares the version of the PeerDist content encoding for which it is configured, as well as the minimum and maximum Content Information Data Structure versions it supports.
HTTP/1.1 200 OK Content-Type: text/html Content-Encoding: peerdist Content-Length: 198 Last-Modified: Fri, 01 Aug 2008 01:02:03 GMT Accept-Ranges: bytes ETag: "8d2babfc81f3c81" Server: Microsoft-IIS/7.0 X-P2P-PeerDist: Version=1.1, ContentLength=184946 Date: Fri, 01 Aug 2008 10:20:30 GMT ...198 bytes of PeerDist Content Information...
In this response, the server indicates that the content is encoded using the PeerDist content encoding. The server used version 1.0 of the PeerDist content encoding. The server could not generate version 2.0 of the PeerDist content encoding because the client specified a MaxContentInformation parameter equal to 1.0. Had the client specified a MaxContentInformation parameter equal to 2.0, then the server could have chosen to respond with version 2.0 of the PeerDist content encoding. The server also includes the content length of the entity-body when it is encoded using the identity content coding. In other words, the Content-Length header field would have had the value 184946 if the Content-Encoding header was either missing or specified "identity" as defined in [RFC2616].
If the server does not have the Content Information Data Structure at the time of the request, the server responds with the original content and includes the X-P2P-PeerDistEx header with MakeHashRequest set to true as shown in the following example.
HTTP/1.1 200 OK Content-Length: 184946 Content-Type: image/png Last-Modified: Thu, 31 Mar 2011 20:17:35 GMT Accept-Ranges: bytes ETag: "c184b9ace0efcb1:0" Server: Microsoft-IIS/8.0 X-P2P-PeerDist: Version=1.1 X-P2P-PeerDistEx: MakeHashRequest=true
In response to the above message, the client sends a hash request with the X-P2P-PeerDistEx header and HashRequest set to true as shown in the following example.
GET /welcome.png HTTP/1.1 Host: www.example.com X-P2P-PeerDist: Version=1.1 X-P2P-PeerDistEx: MinContentInformation=1.0, MaxContentInformation=2.0, HashRequest=true