What Is an Email Worm
In networking, an email worm is a computer worm which can copy itself to the shared folder in system. And it will keep sending infected emails to stochastic email addresses. In this way, it spreads fast via SMTP mail servers.
What Is the Harm of Email Worm
An email worm can send lots of infected emails in a very short time and it will never stop unless it’s removed. It will cause a large traffic and make the system go slowly. Sometimes it even makes the mail server crash.
How to Detect Email Worm
If you are suspicious some host in your network is infected with an email worm, here is a process how we can detect email worm in network with Colasoft Packet Sniffer, step by step.
>Step1. Download a free trial and deploy it properly.
>Step2. Launch a Project and Start Capturing Some Traffic.
>Step3. Switch to “Diagnosis” Tab
Diagnosis tab is a view we can see all the network issues automatically detected by Colasoft Packet Sniffer, also some causes and solutions are suggested.
Diagnosis Tab Screenshot
If there is a host infected with an email worm, we should be able to see SMTP events in the application layer like this:
SMTP Events in Application Layer
>Step4. Locate the Source IP
Possibly the source IP is the host infected with an email worm as it is sending too many emails in a short period of time with SMTP. So let’s locate the source IP in the “Explorer” with the “Locate” shortcut in the right-click menu.
Locate Source IP
>Step5. Switch to “Logs” Tab
Check if the host is sending emails to a large number of recipients in a very short period of time. If so, we can determine the host is infected with an email worm and should be handled immediately. We should be able to see logs in the Tab like this:
View Email Logs in "Logs" Tab
No doubt the final step is to isolate the host and kill the email worm with some AV software
Also there will be some other process to detect email worm with Colasoft Packet Sniffer, this is the shortest one.
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Tags: email worm, howto, Security
Colasoft, with its all-in-one & easy-to-use network analyzer -Capsa, has been known and recognized in network analysis industry. Today let me recommend 5 nice Colasoft network analysis tools to all network administrators, the tools are totally free and very simple but helpful.
- Colasoft MAC Scanner Pro
List MAC addresses and IP addresses in your local subnet in seconds. Network administration will never become efficient before you know exactly who is the user and where is the computer. MAC Scanner Pro will do it for you.Core Values:
.Scan MAC addresses and IP addresses
.Save Scan Results into database for future reference and network maintenance.
.Add attributes (such as users name and physical location of the host) to scan results and save in database.
.Automatically compares new MAC scan results with database records and notifies difference and new records (illegal access).
.Print and Print Review MAC Scan ResultsSpecial Notice:
Colasoft is launching a campaign this month, you can get a license key of MAC Scanner Pro edition for free as long as you recommend a friend to download MAC Scanner free editon successfully.
Find out more information about this ,please go to http://www.colasoft.com/mac_scanner/index.php?act=recommend.
- Colasoft Ping Tool
Colasoft Ping Tool is powerful in supporting to ping multiple IP addresses simultaneously and comparing response time in a graphic chart. Users can view historical charts and save the charts to a *.bmp file. With this build-in tool, users are able to ping the IP addresses of captured packets in a protocol analyzer (e.g. Colasoft Capsa) conveniently, including resource IP, destination IP or both. - Colasoft Packet Builder
Colasoft Packet Builder enables creating custom network packets; users can use this tool to check their network protection against attacks and intruders.Colasoft Packet Builder includes a very powerful editing feature. Besides common HEX editing raw data, it features a Decoding Editor allowing users to edit specific protocol field values much easier. - Colasoft Packet Player
Colasoft Packet Player is a packet replayer which allows users to open captured packet trace files and play them back in the network. It supports many packet trace file formats created by sniffer softwares such as Colasoft Capsa, Ethereal, Network General Sniffer and WildPackets EtherPeek/OmniPeek, etc.Except sending packet files in original interval between loops, Colasoft Packet Player also supports sending packet files in burst mode and defining the delay between loops if the loop count is more than one.
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Tags: colasoft, MAC Scanner Pro, network analyzer
Network security is an infinitely complex and dynamic subject, implementing these simple measures will go a long way to protecting your Organization’s LAN.
1, Run Network Analyzer Frequently.Recommend an easy-to-use network analyzer, Colasoft Capsa.
2, Disable drives 
isable floppy drive access, USB ports and serial ports on networked computers.
3, Restrict Permissions: Windows 2000 and 2003 server allow you to set permissions so that users can’t run downloaded ‘exe’ or other executable files.
4, Block Instant Messenger:IM and its cousins, ICQ and Yahoo Messenger, sends messages and attachments out to a server and then back to its clients. You lose control when this happens.
5, Password Protect Your BIOS:A BIOS without an administrator password is an invitation to mischief.
6, Run AV Software: Run anti-virus software on all your computers.
7, Build Your Defenses: Install a firewall or a proxy server.
8, Beware Of Attachments From Unknown, Untrusted Sources o not open attachments to email unless you trust the sender.
9, Monitor Your Ports:Install a port monitor to prevent your ports from being scanned.
10, Encrypt Wireless Access.
11, Keep Back Office Systems Off The Organization Network
12, Require passwords to be changed frequently
13, Use CTRL+ALT+DEL to logon
14, Keep your networking skills up to date.
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`Brief introduction about the Endpoint view in Colasoft Packet Sniffer
It is divided into Mac endpoint and IP endpoint in Colasoft 6.9. Users can detect the IP/Mac endpoint in the largest traffic in a short time by the endpoint analytics. And also, The system supply clear statistics of traffic ranking(Top 5 IP endpoint under HTTP protocol).
In the Endpoint view, we can see the specific traffic situation clearly of all the hosts(Including a network segment, a Mac address, and a IP address) in the currently network. Like the hosts with the largest total traffic, hosts that send/receive the largest traffic, hosts that send/receive the most packets, etc.
According to this information, we can confirm that if there are Broadcast / multicast storm, and help users detecting the network malfunctions about network slow, network disconnect, worm attack, DOS attack, and all the malfunctions besides.
Application case study
Once we meet the network malfunction or attack, what the most important thing we should pay attention to, is the currently total network traffic, sent/received traffic, network connection etc, to get a clear direction to find the problem. And, all of this information are included in the endpoint view in Colasoft Packet Sniffer 6.9(figure 1):
endponit_view_1
In figure 1 we can make a compositor on the total traffic, network connection and other related information, to find and locate the host with largest traffic or most connections in the network. For example, at present, the host with the largest network connection is , we can locate the host, then check the related connection information(figure 2):
The connection information shown as the figure 2, we can know that has set up a large amount of TCP connection with other hosts, and the destination address and destination endpoint are indefinite, and Many of the state is to connect client requests synchronization.
endpoint_view_2
Next, check the TCP packets, we can check them out in Summary and Graphic as follows:
endpoint_view_3
endpoint_view_4
In the TCP packets information, we found has sent TCP synchronization packet, and the TCP FIN packets and TCP Reset packets are, this is deviant in the network.
Please go to the Colasoft Official FAQ page for more “How-tos”
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Tags: end point, large traffic, network malfunction, traffic analytics
BitTorrent Consumes Big Bandwidth
Based on the working principle of BitTorrent protocol, if somebody is downloading big files with BitTorrent software, it will be a disaster for other users who need bandwidth for business operations as the user will consume large amount of bandwidth, thus causing long time network slowness, intermittence, even disconnections; because meantime the user downloading files from others, others are downloading files from him.
So it is necessary for IT administrators to track BitTorrent user at first place to regain network bandwidth for business operations. Blocking BitTorrent protocol can be one way; this article is to discuss how to how to track BitTorrent user with Colasoft Packet Sniffer.
How to Track BitTorrent User?
>Step1. Download a free trial and implement it correctly
>Step2. Launch a project and start capturing data
>Step3. Find BitTorrent Protocol in the “Protocols” Tab
Track BitTorrent User Screenshot 1
>Setp4. Locate BitTorrent Protocol in the “Explorer”
Use the “Locate” function to locate BitTorrent protocol in the “Explorer” to analyze dedicated data.
Track BitTorrent User Screenshot 2
>Step5. Track BitTorrent User in LAN in the “Endpoint” Tab
This is the way how to track the BitTorrent user in our network and who are connected with him. There is a lot more we can see from this tab, such as how much data has been downloaded and uploaded via BitTorrent protocol.
Track BitTorrent User Screenshot 3
View how many connections have been built in “Matrix”
You’ll be shocked to see how many connections have been built in the “Matrix” Tab. In this case, we can see this user has built more than 1000 connections with other hosts.
Track BitTorrent User Screenshot 4
About BitTorrent
BitTorrent is a peer-to-peer file sharing protocol used for distributing large amounts of data. BitTorrent is one of the most common protocols for transferring large files.
The protocol works when a file provider initially makes his/her file (or group of files) available to the network. This is called a seed and allows others, named peers, to connect and download the file. Each peer that downloads a part of the data makes it available to other peers to download. After the file is successfully downloaded by a peer, many continue to make the data available, becoming additional seeds. This distributed nature of BitTorrent leads to a viral spreading of a file throughout peers. As more peers join the swarm, the likelihood of a successful download increases. Relative to standard Internet hosting, this provides a significant reduction in the original distributor’s hardware and bandwidth resource costs. It also provides redundancy against system problems and reduces dependence on the original distributor.
Next Step
>>Download a Free Trial
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Tags: bandwidth, BitTorrent, howto, traffic
For some purposes we want to monitor MSN chat around the network, for example, parents want to monitor MSN chat of their kids to ensure their safety; bosses want to monitor MSN chat of employees for company assets security and to improve work efficiency by minimizing none-business chat during working hours. You may still remember Colasoft MSN Monitor, now it is called Unipeek MSN Monitor and it is distributed completely Free for none commercial users.
Now let’s see how we can monitor MSN chat with Unipeek MSN Monitor, the free tool.
Step1. Download Unipeek MSN Monitor
Download Unipeek MSN Monitor, the free edition; from the website. As a matter of fact there is no function difference between Unipeek MSN Monitor the free edition and the commercial edition. The only difference is Unipeek MSN Monitor Free Edition only supports 10 MSN accounts maximum, but quite enough for family users.
Step2. Install and Deploy Unipeek MSN Monitor
The installation is quick and simple, just click “next” all the way to complete the installation. But the deployment is somewhat different. As Unipeek MSN Monitor is designed based on Colasoft’s packet capturing technology, so it has to be deployed properly like a packet sniffer if you want to monitor all MSN chat around the network. Of course, you don’t have to do it if you only want to monitor MSN chat of a single computer. To monitor multiple computers, you can install multiple copies.
Setp3. Run it and Start Monitor MSN Chat
After proper installation and deployment, we can start monitoring MSN chat right away.
About Unipeek MSN Monitor
Unipeek MSN Monitor (MSN sniffer) is Free MSN monitoring software for MSN chat monitoring and MSN message archiving. Based on Colasoft’s packet analysis technology, Unipeek MSN Monitor is able to deliver the most accurate MSN monitoring statistics, and automatically record data for future reference. You need only install Unipeek MSN Monitor once to monitor all MSN chats over the local network.
Key Features include:
• Real-time and 24/7 MSN chat monitoring
• Automatically archive MSN messages for future reference
• Export messages of a custom time range
• Customize MSN account list to be monitored
• Unique Conversation Matrix showing account relations
• Support emotion icons, message font size and color.
Download Now
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When you are entering your credit card number, talking with your lover, chatting with your business partners, can you imagine what will happen if everything you are doing is exposing to everybody?
Yes, it is unbelievable but it is quite true, hackers can easily obtain your private information like crecit card number, email logs, chat logs etc. by using some network analytic tools, such as Colasoft Packet Sniffer.
Protect Your Email Secure And Safe
So if we are helpless with our private information from being monitored or stolen? Of course not, to keep data sent via email private, you just need to encrypt it, as only unencrypted content can be monitored by network analytic tools like Network Analyzer. Only the targeted recipient will be able to decipher the message.
How to Encrypt Your Message?
Public key encryption is a special case of encryption, it operates using a combination of two keys: one is a private key, the other is a public key which together form a pair of keys. The private key is kept secret on your computer since it is used for decryption, the public key, which is used for encryption, is given to anybody who wants to send encrypted mail to you.
How Public Key works?
When you send public-key encrypted mail, the sender’s encryption program uses your public key in combination with the sender’s private key to encipher the message. When you receive public-key encrypted mail, you need to decipher it.
Decryption of a message enciphered with a public key can only be done with the matching private key. This is why the two keys form a pair, and it is also why it is so important to keep the private key safe and to make sure it never gets into the wrong hands (or in any hands other than yours).
Why the Integrity of the Public Key is Essential
Another crucial point with public key encryption is the distribution of the public key.
Public key encryption is only safe and secure if the sender of an enciphered message can be sure that the public key used for encryption belongs to the recipient.
A third party can produce a public key with the recipient’s name and give it to the sender, who uses the key to send important information in encrypted form. The enciphered message is intercepted by the third party, and since it was produced using their public key they have no problem deciphering it with their private key.
This is why it is mandatory that a public key is either given to you personally or authorized by a certificate authority.
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Tags: Email Privacy, packet sniffer, Public Key Encryption
Importance of Network Monitoring
Reading network traffic is essential for system administrators, network engineers, and security analysts. At some point there will be a need to read the network traffic directly instead of monitoring application level details. Examples of situations that might require monitoring network traffic are, auditing network security, debugging network configurations, and analyzing usage patterns. For this task we use network monitoring software, or packet sniffers, that sniff the traffic your computer is able to see on the network. What exactly your computer can see really depends on how the network is laid out, but the easiest way to figure out what it can see is just start sniffing.
The most common tool to do the job is readily available. One of the most popular and easy – to – use tool for monitoring network traffic is Colasoft Packet Sniffer.
How to Monitor Network Traffic
As a packet sniffer, Capsa make it easy for us to monitor and analyze network traffic in its intuitive and information-rich tab views. With Capsa’s network traffic monitor feature, we can quickly identify network bottleneck and detect network abnormities. This article is to discuss how we can Monitor Network Traffic with Capsa’s network traffic monitor feature.
1, Monitor Network Traffic in “Summary”
tab
“Summary” is a view that provides general information of the entire network or the selected node in the “Explorer”. In “Summary” we can get a quick view of the total traffic, real-time traffic, broadcast traffic, multicast traffic and so on. When we switch among the node from the explorer, corresponding traffic information will be provided.
(pic 1. monitor-network-traffic-in-summary)
2, Monitor Network Traffic in “Endpoints” tab
In “Endpoints” view, we can Monitor Network Traffic information of each node, both local and remote. With its easy sorting feature we can easily find out which host is generating or has generated the largest traffic.
(pic 2. monitor-network-traffic-in-endpoints)
3, Monitor Network Traffic in “Protocols” tab
“Protocols” view will list all protocols applied in network transmission. In “Protocols” view we can Monitor Network Traffic by each protocol. By analyzing network traffic by protocol, we can understand what applications are using the network bandwidth, for example “http” protocol stands for website browsing, “pop3″ stands for email, etc.
(pic 3. monitor-network-traffic-by-protocol)
4, Monitor Network Traffic in “Conversations” tab
In “Conversations” tab we can Monitor Network Traffic by each conversation and the figure out which conversation has generated the largest network traffic.
(pic 4. monitor-network-traffic-by-conversation)
5, Monitor Network Traffic in “Matrix” tab
“Matrix” is a view that visualizes all network connections and traffic details in one single graph. The weight of the lines between the nodes indicates the traffic volume and the color indicates the status. As we move the cursor on a specific node, network traffic details of the node will be provided.
(pic 5. monitor-network-traffic-in-Matrix)
6,Monitor Network Traffic in “Graphs” tab
If we want to get a trend chart of the network traffic, then we need to use the “Graphs” tab. “Graphs” view allows us view network statistics dynamically in different chart types, such as ling chart, bar chart, and pie chart. By selecting “Utilization” we get a real-time traffic trend chart.
(pic 6. monitor-network-traffic-in-graphs)
As we can see, with Capsa we can not only Monitor Network Traffic in convenience, but also analyze network traffic in deferent levels, thus enables us quickly and efficiently detect network abnormities and troubleshoot network problems.
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Tags: monitor, Network, packet sniffer, traffic
Kismet Screeshot
What is Kismet
Kismet is an 802.11 layer2 wireless network detector, packet sniffer, and intrusion detection system. Kismet will work with any wireless card which supports raw monitoring (rfmon) mode, and can sniff 802.11b, 802.11a, 802.11n, and 802.11g traffic (devices and drivers permitting). Kismet identifies networks by passively collecting packets and detecting standard named networks, detecting (and given time, decloaking) hidden networks, and inferring the presence of non-beaconing networks via data traffic.
Feature Overview
Kismet has many features useful in different situations for monitoring wireless networks:
- Ethereal/Tcpdump compatible data logging
- Airsnort compatible weak-iv packet logging
- Network IP range detection
- Built-in channel hopping and multicard split channel hopping
- Hidden network SSID decloaking
- Graphical mapping of networks
- Client/Server architecture allows multiple clients to view a single Kismet server simultaneously
- Manufacturer and model identification of access points and clients
- Detection of known default access point configurations
- Runtime decoding of WEP packets for known networks
- Named pipe output for integration with other tools, such as a layer3 IDS like Snort
- Multiplexing of multiple simultaneous capture sources on a single Kismet instance
- Distributed remote drone sniffing
- XML output
Typical Uses
Common applications Kismet is useful for:
- Wardriving: Mobile detection of wireless networks, logging and mapping of network location, WEP, etc.
- Site survey: Monitoring and graphing signal strength and location.
- Distributed IDS: Multiple Remote Drone sniffers distributed throughout an installation monitored by a single server, possibly combined with a layer3 IDS like Snort.
- Rogue AP Detection: Stationary or mobile sniffers to enforce site policy against rogue access points.
Download
Kismet can be downloaded here
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Tags: kismet, packet sniffer, wireless
Internet traffic is the flow of data around the Internet. It includes web traffic, which is the amount of that data that is related to the World Wide Web, along with the traffic from other major uses of the Internet, such as electronic mail and peer-to-peer networks.
In case we want to monitor internet traffic generated or is generating in LAN, here is a detailed process how we can do it with Colasoft Packet Sniffer – Capsa.
Again we must make sure the packet sniffer software is correctly implemented so we can capture all the traffic in LAN, if you don’t know how to do it, please make sure you read how to implement a packet sniffer.
First let’s launch a new project with Colasoft Packet Sniffer, then do some online activities, such as chatting, browsing a website, sending and receiving emails, downloading some files. All these activities will generate different kinds of internet traffic. We may keep the project running to continuously monitor internet traffic or stop the project to do some analysis.
To monitor internet traffic, we’d better first select the “Internet Addresses” in the “Explorer” on the left window:
Monitor Internet Traffic Screenshot1
We can see that all the internet addresses are listed by countries, to monitor internet traffic of a specific country, we just need click on it; If we want to monitor internet traffic of a specific IP address within one country, we need to expand the country node and select the IP address in it.
Also we can monitor internet traffic aggregated or internet traffic in real-time
Monitor Internet Traffic Screenshot2
To view what online activities have generated or are generating internet traffic, we need to use the “Protocols” Tab.
Monitor Internet Traffic Screenshot1
We can see there are protocols which separately stand for different internet activities:
HTTP – Website browsing
MSN – online chatting with Live Messenger
POP3 – Email
HTTPS – Website browsing via a secure link
QQ- online chatting with QQ
DNS – Domain Name System
About Capsa
Colasoft Capsa is a network analyzer (packet sniffer or protocol analyzer) designed for network monitoring and troubleshooting. It performs packet capturing, network monitoring, protocol analyzing, packet decoding, and automatic diagnosing. By giving users insights into all of network’s operations, Capsa makes it easy to isolate and solve network problems, identify network bottleneck and bandwidth use, and detect network vulnerabilities. Learn more about Capsa, please visit http://www.colasoft.com/capsa/
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Tags: colasoft, howto, internet, packet sniffer, traffic
Recent Entries
- How to Detect Email Worm with Colasoft Packet Sniffer
- Recommend 5 Nice FREE Network Analysis Tools to Network Admins
- 14 Tips to Protect Your Organization’s Network
- How to detect the network malfunction via the end-point view with Colasoft Packet Sniffer
- How to Track BitTorrent User in Network with Colasoft Packet Sniffer
- How to Monitor MSN Chat with Free Unipeek MSN Monitor
- How Public Key Encryption Can Make Email More Private
- Monitor Your Network Traffic with Colasoft Packet Sniffer
- Kismet, an 802.11 Layer2 Wireless Network Detector and Packet Sniffer
- How to Monitor Internet Traffic with Packet Sniffer
- How to Monitor http Traffic with Packet Sniffer
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