Software

Five free network analyzers worth any IT admin's time

Solid information leads to a strong and worry-free network. Jack Wallen lists five tools that can get you that solid information for free.

If you work on a network, you then know the value of information. Solid information leads to a strong and worry-free network (or at least as worry-free as you can manage). In order to gather that information, you need the right tools. The tools I speak of are network analyzers. Once you start looking, you can find analyzers of every shape, size, and price. But for most network admins, the free tools do a solid-enough job to get you the information you need.

But which of these tools are the best? If you start looking, you'll find plenty available. To help narrow the search for you, I've found five of the best network analyzers available. From this list, you should be able to find the one tool that perfectly suits your needs. With that promise made, let's dive in and see what's what.

This blog post is also available as a TechRepublic Photo Gallery.

Five Apps

1. Wireshark

Wireshark is one of the most powerful network protocol analyzers on the market (free or paid). In fact, Wireshark is often considered the de facto standard among the industry. This analyzer features: Live capture and offline analysis; standard three-pane packet browser; multi-platform (Windows, Linux, OS X, Solaris, FreeBSD, NetBSD, and many others); captured network data can be browsed via GUI, or via the TTY-mode TShark utility. Other features include: powerful display filters; rich VoIP analysis; read/write many different capture file formats; capture files can be compressed with on the fly; live data can be read from Ethernet, IEEE 802.11, PPP/HDLC, ATM, Bluetooth, USB, Token Ring, Frame Relay, FDDI, and others; decryption support; coloring rules; output can be exported to XML, PostScript, CSV, or plain text.

2. NAST

NAST (Network Analyzer Sniffer Tool) is an ncurses-based tool that has, admittedly, not been under development for quite some time. Even so, the tool is quite useful and does a great job of capturing network traffic. I put this tool on the list because it's invaluable if the only machine you have access to is a UNIX GUI-less server. But even if you have a GUI, this tool is quite handy. NAST features: Build LAN hosts list; follow a TCP-DATA stream; find LAN internet gateways; discover promiscuous nodes; reset an established connection; perform a single half-open portscanner; perform a multi half-open portscanner; find link type (hub or switch); catch daemon banner of LAN nodes; control arp answers to discover possible arp-spoofings; byte counting with an optional filter; and write reports logging.

3. Zenmap

Zenmap is the official GUI for the Nmap Security Scanner. Zenmap is available for Windows, Linux, Mac, and BSD. Zenmap can be used to read live captures or save captures for later viewing. With Zenmap you can empower the features of Nmap to help you with: network inventory, managing service upgrade schedules, and monitoring host or service uptime. Features include: Host discovery; port scanning; version detection; OS detection; scriptable interface; web scanning; full IPv6 support; Nping support; fast scanning; and much more.

4. Angry IP Scanner

Angry IP Scanner is another open source, cross platform scanner that is designed, from the ground up, to be incredibly fast and very simple to use. Angry IP offers the following features: Portable (zero installation on certain platforms); ping checks; NetBIOS information; resolves hostnames; determines MAC address; can determine currently logged-in user; plug in system; scan results can be saved as CSV, TXT, XML, or IP-Port list; and fast, mutli-threaded scanning.

5. JDSU Network Analyzer Fast Ethernet

JDSU Network Analyzer Fast Ethernet has a long name and is long in features. Although it has numerous features, you don't have to be a full-blown network analyst to make use of this tool. JDSU allows anyone (of nearly any experience level) to: Quickly determine who is on a network, who is using bandwidth, and where errors may be occurring on the network. You can also identify problems before they become serious issues; use expert analysis tools to solve network problems quickly; capture and analyze network traffic in real-time; and analyze data offline. JDSU offers multi-technology analysis, a consistent user-interface across platforms, and is scalable for distributed analysis.

Bottom line

No matter what your level of expertise, and your network needs, one of these tools should make the gathering of information about your network a simple task. Whether you need a simple, ncurses-based tool, or a full-blown, full-featured GUI, you can find what you're looking for and not have to spend a single penny.

Also read:

About

Jack Wallen is an award-winning writer for TechRepublic and Linux.com. He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website getjackd.net.

11 comments
alterlynn
alterlynn

where i have to download it.I

JetConSys
JetConSys

EMCO Ping Monitor has a freeware version for up to 5 devices. Professional version cost is not prohibitive though. Every other product I have tried showed false failures (pinging as few as 3 devices) or app just stopped pinging with no warning , This product is amazing!

robo_dev
robo_dev

Those wonderful classes Network General used to hold... I am partial to WireShark, as it's the most like the old Sniffer product. The difference between the free products and the commercial products is that the latter have more problem analysis built in so a less technical person can fix a problem faster.

ccaldwell
ccaldwell

Netscan and Iperf/Jperf I use netscan all the time. Love it. It's free and portable. Iperf/Jperf is great for testing speeds between 2 computers. You can setup your own speed testing server!

jlippens
jlippens

Just checking to see if anyone found issue when downloading the AngryIP scanner software...Windows Defender flagged it as malware (Angryscan.a) and wanted to remove it...

mikifinaz1
mikifinaz1

Learning how to use the tools and how they work with the various network OSes.

Rodo1
Rodo1

It comes as a zip package with the install file and two doc files (one .docx and the other .txt) that both have the same unlock code, supposedly. The code does not work; comes up as invalid. Did I miss something? If someone has gotten this code to work, I'd appreciate an answer, or do you have to just use it for 15 days?

yakupm
yakupm

"JDSU offers multi-technology analysis, a consistent user-interface across platforms" - only download I can find is an .exe

leo8888
leo8888

I've been wanting to try a couple new tools for capturing and monitoring network traffic. I tried Wireshark quite a while back but at the time I didn't have much free time to get familiar with it so I think I'll start there with a fresh download of the latest version. I like trying to find new tools to add to my collection so I appreciate these type of articles.

Gmuscle
Gmuscle

I have used several of these tool. Primarily I use wireshark to capute network drops and connections. I will try some of the other tools to see if they provide more information. Thanks