Updated compression RFC

Author: adlrocha

beyond-bitswap/rfc/rfcBBL203A.md

@@ -32,12 +32,14 @@ Some of the compression approaches to be explored in this RFC are:
 ## Implementation plan
 -  [x] Perform a simple test to evaluate the benefits of "on-the-fly" compression on blocks (to determine if IPFS could benefit from directly exchanging compressed messages and blocks). Evaluate different compression algorithms used in the web.
 
-    -  [x] Evaluate the compression of full Bitswap messages (`bs.compressionStrategy = "full"`): To achieve this we add a compression flag in [Bitswap messages](https://github.com/adlrocha/go-bitswap/blob/master/message/message.go) to be able to identify when messages are compressed. Afterwards, if compression is enabled we need to [compress the stream](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/network/ipfs_impl.go#L240) before sending it. Compressed messages are identified in the [newMessageFromProto](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/message/message.go#L199) of receiving peers, they are uncompressed and processed seamlessly by Bitswap. In order to open the door to the use different compression algorithms and different full-message compression strategies a compressionType has been added to [message.proto](https://github.com/adlrocha/go-bitswap/blob/master/message/pb/message.proto).
+    -  [x] Evaluate the compression of full Bitswap messages (`bs.compressionStrategy = "full"`): To achieve this we add a compression flag in [Bitswap messages](https://github.com/adlrocha/go-bitswap/blob/master/message/message.go) to be able to identify when messages are compressed. Afterwards, if compression is enabled we need to [compress the message](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/network/ipfs_impl.go#L240) before sending it. Compressed messages are identified in the [newMessageFromProto](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/message/message.go#L199) of receiving peers, they are uncompressed and processed seamlessly by Bitswap. In order to open the door to the use different compression algorithms and different full-message compression strategies a compressionType has been added to [message.proto](https://github.com/adlrocha/go-bitswap/blob/master/message/pb/message.proto).
 
-    - [x] Evaluate the compression of blocks only (`bs.compressionStrategy = "blocks"`): We compress each block before adding it to the message in [nextEnvelope](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/internal/decision/engine.go#L469) function of engine.go, and then uncompress them in [ReceiveMessage](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/bitswap.go#L458) from bitswap.go. For the compression of blocks, the only thing that is changed for the transmission of the block is the RawData, the CID is kept without change so the block is conveniently identified. It required several changes over unit tests.
+    - [x] Evaluate the compression of blocks only (`bs.compressionStrategy = "blocks"`): We compress each block before adding it to the protobuf message in [ToProtoV1](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/message/message.go#L583) function of message.go, and then uncompress them in [newMessageFromProto](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/message/message.go#L199). For the compression of blocks, the only thing that is changed for the transmission of the block is the RawData, the CID is kept without change so the block is conveniently identified.
 
     -  [x] Use [GZip](https://golang.org/pkg/compress/gzip/) as the default compression algorithm (`engine.compressor = "Gzip"`).
 
+    - [ ] Instead of compressing fields of the protobuf message, evaluate the compression of the full stream in the [bitswap network](https://github.com/adlrocha/go-bitswap/blob/d151875a94048c3db59de52b9cb99d0246d74613/network/ipfs_impl.go).
+
     -  [ ] Evaluate other compression algorithms (Brotli and gzip are the best alternative, but in case we want to test with other algorithms):
 
         - [ ] [ZDAG](https://github.com/mikeal/zdag) Blocks