ssh protocol implementation
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Joined: Jan 2010
04-01-2010, 12:05 AM
hai, can any body guide me in my project and implimentation "high speed bulk data transfer using ssh protocol"
Active In SP
Joined: Jan 2010
05-01-2010, 05:46 PM
SSH is a highly successful multipurpose protocol used for both
interactive shells and transport layer mechanisms. Tatu YlÃƒÂ¶nen of Helsinki University of Technology developed SSH. But most implementations of SSH reduces its
functionality as bulk data transport tool in high performance
network environments.adoption of strong, cryptographically
secure authentication methods for accessing remote systems and
resources came because of the weak security of FTP and telnet. SSH is widely available as both an open source and
commercial product for almost every combination of operating
system and hardware platform in use.The main disadvantage is that transfer
speeds over wide area networks is painstakingly slow.
Window size and performance:
Consider Two identical connections exist between Hosts X and Y.
an undersized window allows only a
small portion of the available network capacity to be
utilized. Whereas window size that
matches the BDP of the p
ath permits full utilization.many users
blame the performance problem on either a failing network or the
overhead imposed by encryption. expect transfers would be slow regardless of this distance between hosts if the processing for encryption was the culprit. But this is not the case.
1. Redefining the Window Size:
This was to redefine
SSH receive window size to some appropriately large value at
compile time.But reasons like filled buffers on intervening routers, overly rapid
saturation of the path causing excessive loss and a return to slow
start before congestion control mechanisms can take effect, cause negative effect.
problem arises if the underlying operating system is using
dynamically sized receive windows, better known as an
3.Layer 4 Awareness
SSH aware of the transport protocol layer (OSI Layer 4).we remove the bottleneck without
necessitating the use of statically defined overly large buffers.
Cryptographic methods require more computation. SSH uses two distinct
cryptographic methods, encryption for privacy and message
authentication for integrity.on distributed
computing networks, users may end up competing for scarce
processor resources if users run concurrent instances of HPNSSH. The performance will be variable in a span of a single transfer which wil be mistaken by users as low performance
provides another possible avenue to enhance throughput
Full seminar and presentation report is available in this link:
psc.edu/networking/project and implimentations/hpn-ssh/papers/a14-rapier.pdf
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion