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NewsVac: News from around the Web
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Scale your file system with Parallel NFS
1 week, 2 days ago
The Network File System (NFS) is inadequate for the demanding input- and output-intensive applications commonly found in high-performance computing—or, at least it was. The newest revision of the NFS standard includes Parallel NFS (pNFS), a parallelized implementation of file sharing that multiplies transfer rates by orders of magnitude. -
Cisco Unleashes Big Routers For Video
1 week, 3 days ago
Cisco claims new ASR 9000 offers the best platform ever for video and other service delivery with Terabits of capacity. -
Implement lower time granularity for retransmission of TCP
1 month ago
Reduce the overhead of per-tick processing with a timer wheel algorithm that implements the retransmission timer. In this article, learn how to get lower granularity with your retransmission timer by using the AIX TCP fast timer, and discover other advantages of lower timer granularity. -
Networks: The Crux of Tomorrow's Datacenter
3 months, 2 weeks ago
Perhaps Scott McNealy was right when he said "the network is the computer" all those years ago, and the next generation of datacenters will bear that out. -
Researchers could face legal risks for network snooping
3 months, 4 weeks ago
A group of researchers from the University of Colorado and University of Washington could face both civil and criminal penalties for a research project in which they snooped on users of the Tor anonymous proxy network. Should federal prosecutors take interest in the project, the researchers could also face up to 5 years in jail for violating the Wiretap Act. -
Meet Squid
3 months, 4 weeks ago
Squid is a caching proxy server that can provide enhanced performance for HTTP and FTP. Squid will cache commonly accessed sites so that it can improve performance by 10-20% for Internet connections. -
Netgear's open wireless-G router for open source hackers
4 months, 3 weeks ago
"NETGEAR has announced a wireless router specifically targeted at the Linux community. The WGR614L is based on a MIPS CPU with 16M of RAM an 4M of flash, along with 802.11g and 10/100 ethernet connectivity. It currently runs Tomato and DD-WRT firmware and will soon add support for OpenWRT." -
From Live Mesh to the Open Mesh
6 months, 3 weeks ago
Marc Canter has written a series of blog posts outlining the issues, constructs, technologies, and standards required to build out an"open mesh." -
Cisco:networking is hot again
6 months, 3 weeks ago
NAC, Trustsec, PCI, Linux and more are all on the table as Cisco VP outlines the network giant's strategy moving forward. -
Why we should care about the spectrum debate
8 months, 2 weeks ago
The debate of who should manage the wireless spectrum and whether it should be open is key to the future of mobile and personal computing, experts say. -
Muni Wi-Fi's second chance
8 months, 2 weeks ago
Wi-Fi networks can work with a little tweaking, a new study finds. -
IPv6 and IPv4 - big trouble coming, and soon
9 months ago
You'll know that most of the Internet runs on IP version 4, the first cut of the Internet Protocol to see widespread use. It was standardised in 1981; for the past twenty five years or so, it's underpinned the beyond-massive expansion of the Internet. -
AT&T to crush copyrighted network packets
10 months, 2 weeks ago
"AT&T says it's time to start filtering copyrighted content at the network level. During a panel discussion at the International Consumer Electronics Show (CES), The New York Times reports, the communications giant joined Microsoft and NBC Universal in arguing that internet service providers - like AT&T itself - should be sniffing your networks packets and blocking anything that copyright holders don't traveling over the wire." -
IPv6 Set for Root Adoption?
10 months, 2 weeks ago
IPv6 adoption has a key adoption deadline looming this year, but is still facing plenty of barriers to adoption. Key among them is this: IPv6 address information is not included in most of the root DNS servers that power the Internet. This makes IPv6 to IPv6 connections a difficult proposition. -
Book review: Linux Networking Cookbook
11 months, 1 week ago
"Linux networking cookbook is a book for both a seasoned and new Linux network administrator. It includes valuable time saving recipes, tools and related resources. The book is written in clear and concise style with tons of examples and working code .... " - More News
Linux.com : Networking
Speed up your Internet access using Squid's refresh patterns
Bandwidth limitation is still a problem for a lot of people who connect to the Internet. You can improve your available bandwidth by installing Squid caching proxy server on your network with configuration parameters that will increase your byte hit rate, giving you about 30-60% more bandwidth.
Access remote network services with SSH tools
You probably rely on the services on your own private network -- wikis, mail servers, Web sites, and other applications you've installed. What happens when you have to leave the friendly confines of your network? With minimum exposure and few simple tools, you can get all of the comforts of home anywhere you can find an Internet connection.
Parallel SSH execution and a single shell to control them all
Many people use SSH to log in to remote machines, copy files around, and perform general system administration. If you want to increase your productivity with SSH, you can try a tool that lets you run commands on more than one remote machine at the same time. Parallel ssh, Cluster SSH, and ClusterIt let you specify commands in a single terminal window and send them to a collection of remote machines where they can be executed.
Enhance your DNS and DHCP services with dnsmasq
When a network is small and most of its users interact chiefly with services on the Internet at large, it's easy to get by simply by assigning numeric Internet Protocol addresses to your nodes rather than names. As the network grows, however, and as internal services (wikis, mail servers, media servers, and more) come online, recalling numeric addresses becomes unwieldy. One solution is to implement Domain Name Server (DNS) and Dynamic Host Configuration Protocol (DHCP) with dnsmasq, and thereby cache external DNS addresses for performance reasons, dynamically assign IP addresses to all of the members of your network, and manage everything from one location. This article shows you how.
Simplify system security with the Uncomplicated Firewall
The Uncomplicated Firewall (UFW) is a new tool from Ubuntu whose goal is to make configuration of the built-in Linux packet filter less complicated and more secure for novice users.
Push and pull network filesystems with ccgfs
The CC Network Filesystem (ccgfs) lets you mount filesystems over the network using either the push or pull model for connections. Most network filesystems use the pull model, where the client mounts a network share and all connections originate from the client. Using the push model for network shares means that all connections originate from the server. The push model has advantages when you want a machine on your network demilitarized zone (DMZ) to access a file server through a firewall.
Umit, the graphical network scanner
Umit is a user-friendly graphical interface to Nmap that lets you perform network port scanning. The utility's most useful features are its stored scan profiles and the ability to search and compare saved network scans. A profile lets you configure how a network scan is performed, change the source information for the scan, and explicitly nominate hosts to include or exclude from the scan, as well as various more advanced options.
Implement load-balancing, port forwarding, and rate-limiting with shd-tcp-tools
shd-tcp-tools provides a collection of tools for port forwarding, load balancing, and rate-limiting TCP connections. They can be useful if you want to offer SSH services but also limit how much of your bandwidth each user can consume, so that a single long-running SCP operation cannot starve the link from your server to the Internet.
Gerald Carter of Likewise talks about LDAP for Linux (video)
Some GNU/Linux desktop deployments require secure authentication from a Windows Active Directory server. Gerald Carter, a long-time member of the Samba team and an enthusiastic free software developer, now works for Likewise. You can learn from this discussion if you are considering becoming a software developer, are looking for a good business model for your free software-based company, or are looking to manage your network more securely.
A hands-on look at Vyatta Community Edition 4 networking software
Vyatta offers hardware and open source software for enterprise-level network infrastructure. Vyatta can turn any 32-bit x86 machine with at least one network interface into a network appliance that handles routing, firewall, and VPN tasks. The company released Vyatta Community Edition 4 in April, with improved scalability and feature enhancements. Large enterprises now have a low-cost alternative to proprietary hardware like the Cisco 7200.
Benchmarking network performance with Network Pipemeter, LMbench, and nuttcp
Network latency and bandwidth are the two metrics most likely to be of interest when you benchmark a network. Even though most service and product advertising focuses on bandwidth, at times the latency can be a more important metric. Here's a look at three projects that include tools to test your network performance: nepim "network pipemeter," LMbench, and nuttcp.
ssh-xfer: Quickly grabbing files over an existing SSH connection
The Secure Shell (SSH) and Secure Copy (SCP) make remotely performing system administration and copying files across secure links a painless operation. SSH and SCP use the same SSH protocol to protect network communications, but they rely on users knowing if they want a shell or to copy a file beforehand. You cannot easily use an existing SSH shell connection to a remote machine and just grab one or two files; if you want the files, you'll have to make another SSH connection for the file copy using SCP -- unless you have ssh-xfer.
autonom.us aims to be think-tank on network service software licensing issues
Network services are one of the fastest growing areas in modern software. However, while network services have much of the convenience of free software, only a minority are available under a free license. In fact, it was only last November that the Free Software Foundation (FSF) released the GNU Affero General Public License for network services. Under these conditions, last week's announcement of the formation of autonom.us, a new activist group "to focus on issues of software freedom in network services," seems overdue. The group's immediate plans are still evolving, but currently, its main goal -- so far as it has one yet -- seems to be as a policy discussion and advocacy group.
The power of cross-platform synchronization
These days there are plenty of ways to back up your computer files. The options are easy when you're dealing with one computer -- just back up your files to an external hard drive and forget about it -- but when several machines are involved, each with a different operating system, things can get complicated. If you frequently work on more than one computer, having access to your synchronized files no matter where you are can also be useful. PowerFolder, a backup and file synchronizing service, helps you cover all your bases, no matter what platform or how many computers you're using.
Avoid latency while editing remote files using bcvi
The ability to run both console and graphical programs securely on a remote system using SSH brings you a great deal of freedom. When the communications link to that remote system has high latency, however, running interactive programs such as a text editor on the remote machine can become a real test of your patience. The bcvi project lets you edit files on a remote system using gvim (or another editor) on your local desktop machine to avoid the latency. Even without latency issues, bcvi is a handy tool when you want to use gvim to edit a file on a server that does not have gvim or the X libraries installed.
Monitoring network performance with GNetWatch
GNetWatch is a network monitoring and performance testing tool that lets you can see the status of hosts on your network, send ping requests of varying size and quality of service to hosts, and investigate SNMP information. GNetWatch includes support for using Wireshark and nmap to snoop packets and investigate hosts on the network.
Patches coming today for DNS vulnerability
Whether you're running Linux, Windows, Cisco, Sun, or other DNS servers, you are at risk from a newly discovered vulnerability. So says Dan Kaminsky, head of penetration testing research at IO Active, who accidently discovered the DNS "design flaw" earlier this year.
An introduction to the Kismet packet sniffer
Kismet is a wireless "detector, sniffer, and intrusion detection system," and one of the growing list of essential open source tools for computer network security professionals. Kismet runs on any POSIX-compliant platform, including Windows, Mac OS X, and BSD, but Linux is the preferred platform because it has more unencumbered RFMON-capable drivers than any of the others.
Investigating strange dialup activity with Wireshark
A controlled dial-on-demand router is a convenient tool. An uncontrolled dial-on-demand router is not. The Wireshark network protocol analyzer helped me track down the cause of some strange and unwanted dialup connections.
Monitoring network performance with speedometer
Speedometer shows a graph of your current and past network speed in your console, letting you see your network connection's up and downstream speed and history at a glance. You can also use speedometer directly on a file to monitor the download performance and history of a specific download instead of all network traffic. When displaying the total network traffic, speedometer is sort of like gkrellm, in that you can see the current and past network performance on a graph, but you can easily run it over an SSH connection without having to set up gkrellmd.
