Free tcp round trip time software for linux

TCP Knocking provides a port knocking implementation.
Often a secure system needs a port open so that only authorized persons can access a particular service and also the service should not exposed to attackers and worms that may use vulnerabilities that exist in the listening server. Port knocking is designed to be used as a complementary service to the existing authentication mechanism. But one of the biggest problems with port knocking is manipulating the firewall with timeouts.
When the correct knock sequence is sent, the firewall is modified for couple of seconds. Having the firewall open automatically for a time period will make any system administrator uncomfortable. TCP knocking attempts to solve the problem by incorporating the knock into the TCP handshake. Tcp knocking is similar to port knocking, but instead sending UDP packets with secret ports, the TCP handshake packets must include secrete codes. It is at least as secure as port knocking and it can be made secure with more hardening.
Modified TCP handshake:
In normal TCP handshake, the client sends the syn packet and chooses a random initial sequence number. The server responds with a packet that has both syn and ack flags set, choosing a random
The modified TCP handshake uses the empty fields in the header. The server does not respond to connection requests without a special code generated along with the syn packet. The server also encrypts the ISN in the ack packet (2) and the final packet of the three-way handshake must have the correct acknowledgment for the servers ISN. The system is further protected from brute-force attacks by closing the connection if the first attempt for the third packet does not have the expected acknowledgment sequence.
Also, rather than use conventional encryption techniques like HMAC for verification, this system uses a file with random numbers as the key. This is because of the limited unused space available in the TCP/IP header which makes HMAC very weak. By using a shared file, the length of the key can be much greater than traditional systems and even though some parts of the key can be revealed by attacks, the server can protect itself from replay attacks.
The handshake:
1) Syn
The syn packet does not use the 32 bit acknowledgment field in the TCP header as it the the first packet to initiate the connection. Further the 16 bit IPID can be used to transmit information. In the current implementation only the 32 bit acknowledgment field is used. Currently the 32 bit ack is derived from a 64 KB file which contains random numbers. The ISN and the source IP address along with the random numbers are used to generate this value.
2) Syn/Ack
The ISN is encrypted using the random numbers from the 64 KB file using the destination IP address as well as a 16 bit random number used as IPID. I do not have code for this part yet.
3) Ack
The client decrypts the syn number from the encrypted syn, the key file, the 16 bit IPID and its own IP address and sends the ack packet. The server closes all connections from the client for couple of minutes if it sends a wrong ack value. Part of the security relies on the fact that the ISN generated by Linux 2.6 is fairly random.
Implementation:
I have implemented only the first part, which is the server expecting secret code along with the first syn packet from the client. Hence it is very possible to brute-force the server. Also the system is designed with the second phase in mind, which is the encrypted Initial Sequence Number in the ack packet and closing the connection if the correct ack is not sent on the first try. I do not have an implementation for that yet. The security will be increased greatly when the second phase is incorporated. Also the ability to detect brute-force attacks can be added to this system.
But the current system can be used for protecting the server from worms and random scanning. The use-case is similar to port knocking but it does not use the ugly system of opening the firewall for a couple of seconds. Vanilla port knocking is susceptible to brute-force attacks as well. Besides, inserting a kernel module to just ssh into your server will increase your mad sysadmin points.
Enhancements:
- TCP knocking with Phase 1 of the protocol was implemented.

tcptrack provides a packet sniffer that displays TCP connections similarly to top.

tcptrack is a packet sniffer, which passively watches for connections on a specified network interface, tracks their states, and lists them in a manner similar to the Unix top command.

It displays source and destination addresses and ports, connection state, idle time, and bandwidth usage.

TCP port scanner is a network scanner for Linux.

Installation:

1. Install - become root and gunzip/tar tcpscan-X-Y-Z.tar.gz.
2. Type ./confugure , make
3. Type install
4. Enjoy and try type tcpscan localhost
5. To get help - run tcpscan without parametres.

Usage:

tcpscan [-f] [hostname || IP_address]
tcpscan [-f] [first_IP_address] [last_IP_address]

Splendid City Team Sports Scheduler, and Sports Scheduling Software System is useful for people who organize team sports or game events. It can manage sports schedules of any size and complexity. Simply fill in the requested information into the wizard like interface, and Splendid City automates the season, tournament, league, match, round-robin and practice schedules.

A great first step and time saving tool for anyone who frequently does organizational sports scheduling. Splendid City can schedule sports with any user specified combination of dates and times. Create professional double or single elimination tournaments brackets, round-robin league schedules, swiss round tournaments, cross divisional or practice schedules for any sport that requires pairings.

It features options that include the ability to set team and field constraints, game lengths; configurative time management utilities to help you organize events the way you would like; object constraint sharing; automatic schedule generation and re-generation; configurative project web site creation, tournament brackets; publishing via FTP, export to HTML, CSV, iCalendar, XML; import from CSV; standings support with tie-breaker formulas; contact management; import teams, fields, officials, players and player rosters from other users projects ; constraint and conflict checking and resolution.

Users can freely exchange all data associated with projects with other users who have a free copy of Splendid City Lite installed regardless of platform. The application comes with an integrated e-mail client that can aid with the exchange of object files among organization members. There is also a simple FTP client for direct uploading to web domains from within the schedule view frame.

The scheduler gives you complete control over all aspects of the schedule, and creates solutions effortlessly and elegantly in accordance with the user data entered. It can be custom-tailored, and with repeated use via a plugin interface, can be made to automatically accomplish users unique scheduling needs.

The user experience is interactive and straight forward. The application comes fully documented with a built in searchable help system to provide answers to implementation questions.

Privbind is a small tool allowing secure running of unprivileged programs, but allowing them to bind to privileged (<<less