network-protocols

Maximum number of bytes that can be sent on a TCP connection

I initially assumed that since tcp has a sequence number field of 32 bits and each byte sent on a tcp connection is labeled with a unique number, maximum number of bytes that can be sent on a tcp connection is about 2^32-1 or 2^32-2 (which?). but now I feel that since TCP is a sliding window protocol, the wraparound of sequence numbers ...

How can I calculate an optimal UDP packet size for a datastream?

Short radio link with a data source attached with a needed throughput of 1280 Kbps over IPv6 with a UDP Stop-and-wait protocol, no other clients or noticeable noise sources in the area. How on earth can I calculate what the best packet size is to minimise overhead? UPDATE I thought it would be an idea to show my working so far: IPv6 ha...

Does Wifi have any form of forward error correction?

I have what I suspect is a malfunctioning wireless access point, the symptom of which is that OS X occasionally says 'your connection may be compromised' and disconnects for a minute. As far as I can see by looking at dmesg lines which say AirPort: Message Integrity Failure detected (G) this indicates that some decrypted packet has ...

Understanding protocols

Hi, guys need some insight here. I know the definition of a protocol, being new to this c++ programming is quite a challenging task.I am creating a Multi-threaded chat using SDL/C++, this is a learning experience for me and now i have encounter a hump in which I need to overcome but understanding it is a little more difficult than I had...

process of connecting RTP with SIP via SDP & land lines

Hello to everyone, I have a problem with starting a media session and to combine it with my SIP client. I've designed a recursive SIP client that reuse the same request template to send the next requests to server, according to the acceptable sequences noted in the RFC's, and examples that I read. as far as I could tell the SIP part is ...

Developing a project which is an implementation of an open standard/protocol

Hi, A lot of interesting code/projects are implementations of protocols, eg SNMP. How are projects like these, which depend on implementing a certain format, developed? Is the process something like get the guidelines of the protocol and then implement code which follows it. For example, XML-RPC is about transmitting XML docs between ...

Looking for good SIP Book

Hey guys I am looking for a SIP book similar to this one on XMPP - Professional XMPP Programming with Javascript and Jquery (http://www.amazon.com/Professional-Programming-JavaScript-jQuery-Programmer/dp/0470540710) I am new to the area and any resources would be appreciated, thanks ...

A smart UDP protocol analyzer?

Is there a "smart" UDP protocol analyzer that can help me reverse engineer a message based protocol? I'm using Wireshark to do the sniffing, but if there's a tool that can detect regularities in the protocol (repeated strings, bits of the protocol that are CRC/Checksum or length, ...) and aid the process that would help. ...

UDP traffic effect on network performance

well, i have network that each proxy (lets assume we have 200 proxies), send UDP packages every constant amount of time. (let assume 10 seconds) to constant amount of hosts (lets assume 10) my question is how will 6 * 10 seconds * 200 proxies * 10 target hosts = 120,000 UDP roundtrip communication per minute will affect my network, in te...

zigbee vs bluetooth

Hey guys We all know about bluetooth cos its more popular. But why is it popular? After reading about Zigbee i found out that it has lower power consumption, higher range in terms of distance and costs lower and is simpler! So why dont we have Zigbee enable phones? Also I would like to know a per device cost estimation between bluetoot...

What does it mean when a DataInputStream keeps returning 0?

I have a DataInputStream, created from a Socket in Java. The connection is to a simple web server that uses chunked transfer encoding. The web server does in fact work in normal browser. But in my program, I am attempting to read, I read the first first bytes (some 5kb of data). But each read after that returns 0 bytes read. Isn't it sup...

Java HTTP Client Request with defined timeout

Hello, I would like to make BIT (Built in tests) to a number of server in my cloud. I need the request to fail on large timeout. How should I do this with java? Trying something like the below does not seem to work. public class TestNodeAliveness { public static NodeStatus nodeBIT(String elasticIP) throws ClientProtocolException, IO...

Apache HttpClient CoreConnectionPNames.CONNECTION_TIMEOUT does nothing ?

Hi, I get strange behavior from HttpClient with parameter CoreConnectionPNames.CONNECTION_TIMEOUT set to 1. I would expect that HttpGet request would fail, throwing connection timeout exception and yet they are successful. This seems irrational as it actually means that TCP handshake finished in less then 1 millisecond. The httpclient ...

Google App Engine, Secure Data Connector (SDC), and supported protocols

I've been investigating what I can do with Google's Secure Data Connector and App Engine. Is it possible, from an App Engine application, to grab resources inside my corporate intranet without using HTTP(S)? From what I read in the documentation, the only way to request resources through SDC is by using url_fetch, which is limited to H...

OS-independent Inter-program communication between Python and C

I have very little idea what I'm doing here, I've never done anything like this before, but a friend and I are writing competing chess programs and they need to be able to communicate to each other. He'll be writing mainly in C, the bulk of mine will be in Python, and I can see a few options: Alternately write to a temp file, or succe...

Difference between message-oriented protocols and stream-oriented protocols

I am trying to understand the difference between these two computer networking terminologies. I searched over the internet but coudn't get a good idea. Could anybody please explain me or give a link to a page that explains this? Thank you... ...

Books for transport layer protocol implementation in Computer Networks

Hello. I am trying to implement a transport layer protocol for my project. I am going to use Linux as my operating system. Could you please suggest me some books or links that explain the implementation of transport layer (like TCP)? Thank you.. Thanks, Bala ...

How are paths determined on a remote machines?

How are paths determined on a remote machines? I have been assigned a network loaction. Let's call it \wassup\test1 I assume that wassup is the ame of the computer. The question I have is this. How can I determine what the local path from the point of view of the remote machine would be for "test1". For example, how would I know if...

socket.error: [Errno 10054]

import socket, sys if len(sys.argv) !=3 : print "Usage: ./supabot.py <host> <port>" sys.exit(1) irc = sys.argv[1] port = int(sys.argv[2]) sck = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sck.connect((irc, port)) sck.send('NICK supaBOT\r\n') sck.send('USER supaBOT supaBOT supaBOT :supaBOT Script\r\n') sck.send('JOIN #darkundergro...

C# Detect Localhost Port Usage

In advance, thank you for your advice. I am currently working on a program which uses Putty to create a SSH connection with a server that uses local port forwarding to enable a client, running my software, to access the service behind the SSH server via localhost. IE: client:20100 -> Internet -> Remote SSH server exposed via router/fi...