custom-protocol

I've been trying to implement a protocol parser in haskell and I'm pretty new to the language, especially when it comes to monads. I've been using binary-0.5.0.2 and have described the header and all the payloads of my protocol. the messages I'd like to parse look something like the following: header + (payload A, payload B, ..) where a field in the header specifies what type of payload the message has. I have had success in parsing the first message in the bytestring, but am at a loss with how to go about reading the next messages, discarding the bytes that were read in processing the first

Apologies if this is answered elsewhere; couldn't find enough information to convince myself of the best way to do this. I also realize this is a lengthy explanation with no code, but let me know if I should whip up some sample code to help demonstrate what I'm doing. Basically: implementing a communication protocol in Java using System.in/out current approach is implementing a state pattern where a Scanner is instantiated on System.in in the context class concrete states invoke a context method to read from the Scanner, and subsequently perform actions/transition states appropriately based on

Are there any open source, high level tools that would facilitate and simplify development of experimental network protocols (TCP/UDP) using a GUI? Basically, something like a dynamic state machine editor that would allow you to define "packets", "messages", "states", "validators", "handlers" etc. Preferably, such a tool would be comprehensive enough to deal with all relevant aspect of the protocol (i.e. client & server), so that the high level protocol description could be serialized out to an XML/RDF file where it could be used to dynamically create application code to implement the protocol