In each network scenario, TCP hole punching operates in a similar way to UDP hole punching. For example, if two peers A and B are behind different NATs, each peer’s first SYN packet sent to the other peer opens up a hole associated with its public address in its respective NAT. If A’s first SYN … Read more
I’ve used both uIP and lwIP extensively. uIP Great if youre only wanting something basic like a bootloader Small footprint. Uses polling so we’ve never got over 3kbit with it 🙁 No DHCP ‘out of the box’ Poor UDP support lwIP Fully interrupt driven so much faster (~ x10) Includes DHCP with failover AutoIP UDP … Read more
This all depends on what you want to focus on. From your question, the thing you are most interested in is the data flow throughout the different layers (user-space stream -> voltage on the cable). For this, I propose you use http://www.csse.uwa.edu.au/cnet/, which is a full network simulator. It allows you to step through all … Read more
C++ Unit Testing With Boost.Test (permanent link: http://web.archive.org/web/20160524135412/http://www.alittlemadness.com/2009/03/31/c-unit-testing-with-boosttest/) The above is a brilliant article and better than the actual Boost documentation. Edit: I also wrote a Perl script which will auto-generate the makefile and project skeleton from a list of class names, including both the “all-in-one” test suite and a stand alone test suite for … Read more
Try scapy. It is a very powerful program for packet inspection, manipulation and creation. You can use it to build your own tools.
If you’re asking if you can use UDP as a Layer 2, then the answer is yes, sort of. There are various protocols that allow you to create a tunnel to another network using a UDP transport, such as L2TP and even IPsec (with NAT traversal). You could also do it at the application layer. … Read more
Since there seems to be some interest in this question I decided to update the question with a answer with details on how this problem was eventually solved. First some background. I inherited this code from a previous developer and my role was to get the broken code to work. I spent a lot of … Read more
I know this is an old question, but this is now explained at nodejs.org here: The worker processes are spawned using the child_process.fork method, so that they can communicate with the parent via IPC and pass server handles back and forth. When you call server.listen(…) in a worker, it serializes the arguments and passes the … Read more
As explained here: Domain name servers store information about part of the domain name space called a zone. The name server is authoritative for a particular zone. A single name server can be authoritative for many zones. Understanding the difference between a zone and a domain is sometimes confusing. A zone is simply a portion … Read more
Using io_service::poll instead of io_service::run is perfectly acceptable. The difference is explained in the documentation The poll() function may also be used to dispatch ready handlers, but without blocking. Note that io_service::run will block if there’s any work left in the queue The work class is used to inform the io_service when work starts and … Read more