CS3700-project2/README.md

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2020-02-02 04:20:04 +00:00
2020-02-02 05:52:28 +00:00
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## High level approach
The design of this "BGP" router is based on an internal radix tree structure containing the routing
database. Routes are indexed in the tree based on the bit pattern of their subnet, and route lookup
walks the tree to find the most specific route node corresponding to the requested destination
address. The router itself is based on Racket's built-in I/O multiplexing to automatically manage
I/O between multiple sockets.
## Challenges
- **No existing radix tree package in Racket.**
Due to Racket's unfortunate lack of adoption in the networks field, nobody has written any public
radix tree library for Racket that we could find, so we had to implement our own. This went
through approximately 3 iterations and it's still mildly spaghetti code.
- **No stdlib `SOCK_SEQPACKET` support.**
There's no support for `SOCK_SEQPACKET` in the standard UNIX domain socket module, so we pulled
the source code for this module and added a mode for `SOCK_SEQPACKET`.
- **Interesting simulator dependencies.**
The provided simulator has a hard dependency on Python 3.6, which neither of us actually had
installed or were capable of installing, and it did not work with Python 3.8.
## Testing
For the milestone submission, we included some basic internal unit tests but there isn't a lot of
code coverage on those yet. We also ran the simulator milestone tests against the current router
implementation and both milestone tests are passing.