One customer reported that BBC online video can not be blocked by WFilter, even "Block Online HTTP Video and Downloading of Video Files" is checked in certain blocking levels. So we did some research and found, other than HTTP protocol, the BBC websites also use the RTMP (Real Time Messaging Protocol) to play online video. Because blocking of RTMP is not supported by default in WFilter(will be added soon), this tutorial will guide you to block BBC online video by the "Customize Protocols " feature of WFilter.
First, Add a new protocol named "RTMP".  1. Protocol Settings: Protocol Name: RTMP Protocol Desc: Real Time Messaging Protocol Type: Streaming 2. Pattern1 Name: RTMP_HTTP Desc: RTMP_HTTP Type: HTTP SEND Offset: 0 Format: User-Agent Content: Shockwave\sFlash 3. Pattern2 Name: RTMP Desc: RTMP Type: TCP_SEND Offset: 0 Begin Byte: 03 Format: 0 Content: \x03[\x00-\xff]{4}\x80\x00 Second, Enable blocking of RTMP in certain blocking levels. Now, BBC videos will be successfully blocked. Related Topic: How to block bbc iplayer?
Internet can be a benefit to business when used properly, but internet
is often abused by employees and poses significant liability and
security risks. Used
improperly, the Internet can subject every organization to harassment claims,
countless hours of lost productivity and innumerable security leaks and
vulnerabilities. Several important risks caused by improper internet usage: 1. Virus Infection 2. Lost Productivity 3. Legal liability 4. Bandwidth consumer So it is necessary for you to restrict employees internet access on your network. To achieve this goal, first you need an internet access policy, which should be able to: 1. Clarify what constitutes acceptable use of Internet services. 2. Ensure employees understand who to contact with questions regarding acceptable use. 3. Ensure employees understand the penalties that arise from Internet misuse. 4. Help lessen an organization's spyware and virus infestation rates. 5. Provide human resources with signed documentation from each employee stating a pledge not to improperly use Internet services. 6. Help mitigate productivity losses. 7. Decrease dependence upon technology solutions used to enforce employee behavior. 8. Reduce the organization's liability resulting from harassment claims, copyright violations originating onsite and other illegal acts. You also need an internet filtering product to assure your internet policy. Let's take "WFilter Enterprise" as an example, it enables you to monitor and filter internet access for all computers from a mirroring port of your switch. You only need to install WFilter in one computer to monitor the whole network. Key Features:
- Keep a detailed record of each web surfing and web posting.
- Record all incoming and outgoing email content and attachment.
- Monitor and archive instance messengers chat contents and activities.
- Monitor and archive files transferred by web, ftp and IM tools.
- Implement a policy to filter internet access during working hours.
- Websites, messengers and p2p file downloading can be blocked to save bandwidth and raise productivity.
- You only need to install WFilter in ONE computer to manage your whole network.
http://www.imfirewall.us
Sometimes you may want to block facebook games during working hours. This tutorial will guide you to block facebook games using "WFilter Enterprise". First, add a website black list. Second, choose this website black list in certain blocking policy.
Third, apply this blocking policy to certain computers.
Now, facebook game is blocked.
BBC iPlayer (formerly known as Integrated Media Player (iMP), Interactive Media Player, and MyBBCPlayer) is an internet television service, P2P, cable television, and several mobile devices developed by the BBC to extend its existing RealPlayer-based "Radio Player" and other streamed video clip content. As online iPlayer may consume much internet bandwidth, this tutorial will guide you to block BBC iPlayer using WFilter. We suppose WFilter is already properly installed and is capable of monitoring/blocking other computers, if not, please read How to monitor internet usage on company network first. WFilter's "website black list" is based on website domains, so we can not use "website black list" to block iPlayer, since iPlayer is a subfolder of www.bbc.co.uk without a individual domain. However, we still can use "URL Keywords Filtering" feature to block url with certain keywords. The below example demonstrates blocking of url with keyword "iplayer". 1. Create a blocking policy, and enable "URL Keywords Filtering". 2. Choose "Streaming Media" category and click the edit icon to edit its keywords list. Please notice: WFilter already has some default keywords(the default
keywords are hidden). For example, "video" is already included in the
"Streaming Media" category. If you only want to block "iplayer", you can add a new category in "Category Settings"->"Customize Categories" of WFilter. In this example, we need to add "iplayer" to the keywords list:  3. Apply this blocking policy to certain computers.  4. By now, urls with keywords "iplayer" will be blocked. More information, please check "WFilter Enterprise".
Other related links: How to block internet downloading?How to monitor internet usage on company network?Internet monitoring software for businessHow to filter web surfing?How to block websites and restrict internet access?How to Block Bittorrent and bitcomet? How to block msn file transfer?How to block certain websites to save your productivity? How to block AIM using WFilter?
Some switches does not allow outgoing traffic on a mirroring port. In this case, WFilter needs a separate blocking adapter to send blocking packets. And if you're monitoring and filtering more than 100 computers, we recommend you to use a different blocking adapter as the monitoring adapter. When the two network cards are installed, we will want the Windows system to use the blocking adapter to access your network. However, sometime the Windows system might pick up the monitoring adapter and fails to connect to your network. This problem can be resolved by the "Automatic Metric" setting in Windows. A metric is a value that is assigned to an IP route for a particular
network interface that identifies the cost that is associated with
using that route. The Automatic Metric feature is configured independently for each network interface in the network. This feature is useful in situations where you have more than one
network interface of the same speed, for example, when each network
interface has been assigned a default gateway. In this situation, you
may want to manually configure the metric on one network interface, and
enable the Automatic Metric feature to configure the metric of the
other network interface. This setup can enable you to control the
network interface that is used first in the routing of IP traffic. In our case, the "Automatic Metric" of the blocking adapter shall be smaller than the monitoring adapter. So by setting "Automatic Metric" of the blocking adapter to "1", and the monitoring adapter to "2", Windows system will use the blocking adapter to access your network.   
You may assign static ip addresses to computers manually or in your DHCP server. However, it is difficult to prevent users from changing their ip addresses or mac addresses. Though it is more reasonable to setup ip-mac binding in routers or switches, software solution is also a good option, as it is easier to setup and manage. This tutorial will guide you to bind ip addresses to mac addresses in WFilter, an internet filtering and monitoring software product. First, you need to setup a mirror port in your switch to do monitoring. For how to deploy internet monitoring and filtering, check this guide: How to monitor internet usage?Second, in "Control Settings"->"IP Management" of WFilter, you can setup ip-mac binding just by a few clicks.  i When ip-mac binding is setup, internet access will be blocked when the user tries to change ip address or mac address.
Unmanaged websites surfing is killing your productivity. And your computer and network is open to attack when visiting harmful sites. So it is important to block unwanted websites in your network. Blocking of websites can be done in many ways. These include using free software and windows settings. There are even many add-ons for browsers like Firefox which let you check and restrict websites. This tutorial will guide you to filter and block websites access in 4 ways. 1. host.cfg In "Local Disk (C:) > WINDOWS > system32> drivers > etc", you will find a file named "host.cfg". The Hosts file contains the mappings of IP addresses to host names. This file is loaded into memory (cache) at startup, then Windows checks the Hosts file before it queries any DNS servers, which enables it to override addresses in the DNS. This prevents access to the listed sites by redirecting any connection attempts back to the local (your) machine. You may use "notepad.exe" to edit this Hosts file. Example - the following entry 127.0.0.1 ad.doubleclick.net blocks all files supplied by that DoubleClick Server to the web page you are viewing. 2. Opendns OpenDNS offers DNS resolution for consumers and businesses as an alternative to using their Internet service provider's DNS servers. By collecting a list of malicious sites, OpenDNS blocks access to these sites when a user tries to access them through their service. OpenDNS enables you to block websites by 50+ categories. OpenDNS also provides whitelist and blacklist features to enable you to create exception cases ("always allow" and "always block") to complement category-based filtering. To use OpenDNS service, you need to change your DNS server settings manually. More information, please visit http://www.opendns.com3. Router, Firewall or UTM If you have a powerful router or UTM device, you also can setup web filtering on it. For more information about UTM solution, please visit http://www.astaro.com4. Internet filtering products You also can use internet filtering products to do web filtering. An internet filtering product can be deployed in your network, and it enables you to monitor, filter and block internet activities of all computers from a mirroring port. More than web filtering, internet filtering product can also block file downloading, block p2p traffic and block messenger. For internet filtering software, you can try "WFilter Enterprise", http://www.imfirewall.us
Unmanaged websites surfing is killing your productivity. Employees may spend hours to read news, watch online video and play online web games. So, to save productivity, it is necessary for organizations to block certain websites and restrict internet access. You need to implement an internet policy as: 1. Only work-related websites are allowed during work time. 2. Destructive websites like violence, adult, shall be blocked always. 3. Downloading websites shall be blocked to save bandwidth if you are suffering from slow internet speed. However, in today's internet, a website can not be blocked only by blocking its ip address or domain. It is still accessable by: 1. Open proxy servers. 2. Third party tunneling proxy service. 3. Tunnel VPN service. To make your blocking effecient, you also need to block certain proxy/tunneling protocols. WFilter makes it simple to block websites and proxy service. 1. Filter certain websites
You can filter certain websites by "website black/white list" and "website category":   2. Block Proxy Service and VPN protocols.WFilter supports proxy protocol transparently. No addtional setting is required to block open proxy server. You may setup a "HTTPS black/white list" to block unwanted VPN.  More information, please check "WFilter Enterprise". Other related links: How to block video streaming on company network?How to block internet downloading?How to monitor internet bandwidth?How to monitor internet usage on company network?Internet monitoring software for businessHow to filter web surfing?
Online audio/video streaming can consume most of your bandwidth. To save your bandwidth, you might want to block online steaming traffic on your network. Generally speaking, online streaming can run on different protocols: 1. Video websites, like youtube. You can watch video directly on the webpages. 2. Standard Real Time Streaming Protocol(RTSP). 3. P2P based streaming products, like pplive, ppstream. 4. Video downloading websites. Therefore, for complete blocking of video streaming, you need to block all above video traffic. First, block "streaming" category websites: Second, block downloading of video files: Third, blocking RTSP and other online streaming protocols: More information, please check "protocols supported by WFilter". Other related links: How to block internet downloading?How to monitor internet bandwidth?How to monitor internet usage on company network?Internet monitoring software for businessHow to filter web surfing?How to block websites and restrict internet access?How to Block Bittorrent and bitcomet? How to block msn file transfer?How to block certain websites to save your productivity? How to block AIM using WFilter
Unmanaged internet downloading can consume most of your bandwidth, In practice, many, often most, of the files shared on peer-to-peer
networks are copies of copyrighted popular music and movies.
So, it is important for corporations to manage, control and block p2p traffic and block unwanted file downloading. Files can be downloaded via various ways as described below: 1. Downloading from HTTP/FTP websites. 2. Downloading from p2p networks.
3. Downloading from instant messenger buddies. For security purpose, downloading from p2p networks shall be completely forbidden in company networks. And only HTTP/FTP downloading from trusted websites can be allowed. Instant messenger file transfer makes it convenient to share files with our friends. It is fast and secure. However, because IM is so popular, virus writers can use it to spread malicious programs. These viruses are spread, in most cases, when a person clicks a link or opens an infected file that was sent in an instant message that appeared to come from a friend. Therefore, messenger file transfer also put your network in danger. "WFilter Enterprise" makes it simple to manage file transfers between local network and the internet. Using WFilter, you may: 1. Limit file downloading size. 2. Block web downloading by file type. 3. Block web downloading by content type. (Mime type) 4. Block p2p traffic. 5. Block file transfer via messengers. Figures: 
 Other related links: How to monitor internet bandwidth?Internet blockingHow to filter web surfing?How to monitor internet usage on company network?Internet monitoring software for businessInternet monitoring software
Unmanaged internet access is harmful to your business. Without proper internet monitoring and filtering, you may suffer from: 1. Lower productivity. Your employees might take hours for web surfing, chatting and watching videos. 2. Slow internet speed. P2P programs or IPTV programs can easily consume most of your bandwidth. So normal business will not have enough available bandwidth. 3. Unmanaged downloading will bring virus, worms and spyware, which is harmful to your network. 4. Leaking of business documents and materials. Therefore, it is important for you to monitor and manage employees internet activity. This guide will introduce you several aspects of deployment and usage of internet monitoring and filtering software. Please be aware that I am only going to talk about internet access monitoring, which does not include screen monitoring, USB forbiding and keystroke recording. The latter requires you to install a client agent in every computer. And internet monitoring only needs to be installed near the internet entrance. How to deploy internet monitoring software? Though internet monitoring only needs to be installed near internet entrance, it is quite different for different network topologies. For "Router<->Switch<->Computers" networks, you need to setup a mirroring port in the switch to enable monitoring. If you are using ISA or wingate proxy server, you can do monitoring right in the proxy server. How to monitor internet bandwidth? Upon properly deployed, you can easily monitor internet bandwidth and activities using internet monitoring software. Below let me take "WFilter Enterprise" as an example: Use WFilter's "Active Connections" feature, you can have a clear view of all connections in your network.  Connections of a particular computer, you can kill established connections if you want. 
For more details about "monitor internet bandwidth", please refer to: How to monitor internet bandwidth?
How to monitor internet usage?In "Online computers" of WFilter, click the numbers under each title to view detailed records.  
How to block downloading?To save bandwidth, inproper downloading shall be blocked. The below figure shows blocking of large size files and blocking by video files. Blocking of video files. For more details, please refer to "How to block downloading?".
Introduction
WFilter supports various ways to filter web surfing activity:
- Block Web Surfing Completely
- Enable Website Black/White List
- Enable URL Keywords Filtering
- Enable Website Category Access Policy
- Websites Exception List
- Enable HTTPS Black/White List
When enabled, all HTTP web surfing will be blocked, except for domains in the "Websites Exception List".
1.1 Add a new blocking level, as in the below figure:
 Figure 1 1.2 Set a proper "Level Name" and "Level Desc", check the "Block Web Surfing". If you want to display a blocking page when blocked, you need to enable "Display a Deny Page When Blocking", as in Figure 2:  Figure 2 1.3 Apply this new blocking level to certain users in "User-computer Table", as in the below figure:
 Figure 3 1.4 Websites will be blocked, as in Figure 4:  Figure 4  Figure 5 Website black/white list can set black list or white list for websites based on domain name.
When black list is enabled, websites in the black list will be blocked. When white list is enabled, only websites in the white list can be visited.
2.1 Add a new blocking level, as in the below figure:
Figure 6 2.2 Set a proper "Level Name" and "Level Desc", check the "Enable Website black/white list", as in Figure 7: Figure 7 2.3 Add certain websites into a black list, as in Figure 8:  Figure 8 2.4 Apply this new blocking level to certain users in "User-computer Table", as in the below figure:
Figure 9 2.5 Websites in the black list will be blocked, as in Figure 10: Figure 10 Figure 11 URL keywords filtering can filter webpages by url address. Using this feature, you can block searching for certain keywords in search engines.
3.1 Add a new blocking level, as in the below figure:
Figure 12
3.2 Set a proper "Level Name" and "Level Desc", check the "Enable URL Keywords Filtering", as in Figure 13: Figure 13 3.3 Check the keywords category to be blocked, as in Figure 14:  Figure 14 3.4 Apply this new blocking level to certain users in "User-computer Table", as in the below figure:
Figure 15 3.5 In this example, searching for "game" will be blocked, as in Figure 16 and Figure 17: Figure 16  Figure 17 Website category access rules can filter websites based on websites categories. Four filtering modes are supported: "Allow", "Deny", "Warn" and "Time Quota".
4.1 Add a new blocking level, as in the below figure:
Figure 18 4.2 Set a proper "Level Name" and "Level Desc", check the "Enable web category rule", as in Figure 19:  Figure 19 4.3 Set certain filtering mode for certain categories, as in Figure 20:  Figure 20 4.4 Apply this new blocking level to certain users in "User-computer Table", as in the below figure:
Figure 21 4.6 In this example, time quota is enabled for "Game" websites, as in Figure 22:
 Figure 22 Websites in the exception list will not be blocked by other rules.
 Figure 23 Above functions can only filter HTTP websites, to block HTTPS websites, you need to enable the "HTTPS Black/White List".
6.1 Add a new blocking level, as in the below figure:
Figure 24 6.2 Set a proper "Level Name" and "Level Desc", check the "Enable HTTPS Black/White List", as in Figure 25: Figure 25 6.3 Add certain websites into a HTTPS Black list, as in Figure 26:  Figure 26 6.4 Apply this new blocking level to certain users in "User-computer Table", as in the below figure:
Figure 27 6.5 As in Figure 28 and 29, certain HTTPS websites will be blocked.  Figure 28  Figure 29 |
WFilter Monitoring Performance
WFilter is designed to monitor a network with no more than 1000 computers, and the available internet bandwidth of the entire network shall be no more than 100Mbit/s. Since WFilter is software, the performance depends a lot on the hardware performance. Higher bandwidth requires faster CPU, and more monitored computers require more RAM. Therefore, we recommend you to provide 1M available RAM for each monitored computer. Below is a performance test result for HTTP request of WFilter 3.3 file-based version:
| # | Computers | Bandwidth | Total HTTP Requests | Recorded Percent | CPU | Memory |
|---|
| 1 | 50 | 37.2M | 16000 | 100% | 35% | 260,298K |
| 2 | 100 | 35M | 20000 | 100% | 38% | 280,576K |
| 3 | 200 | 31M | 40000 | 100% | 58% | 294,561K |
| 4 | 400 | 33M | 80000 | 100% | 68% | 372,786K |
| 5 | 600 | 32.3M | 120000 | 100% | 80% | 540,151K |
| 6 | 1000 | 32.6M | 200000 | 60% | 99% | 540,664K |
As we can see from the above table, when monitored computers number reachs 1000, the "recorded percent" decreased to 60% suddenly. And we noticed the memory only slightly increased, so it shall because lack of memory. Therefore we added the monitoring computer RAM to 2G, and do the test again:
| # | Computers | Bandwidth | Total HTTP Requests | Recorded Percent | CPU | Memory |
|---|
| 7 | 1000 | 32.7M | 200000 | 100% | 90% | 820,640K |
And the test of WFilter 3.3 database version(SQL Server) performance has the similar result:
| # | Computers | Bandwidth | Total HTTP Requests | Recorded Percent | CPU | Memory |
|---|
| 1 | 50 | 34.9M | 10000 | 100% | 45% | 197,392K |
| 2 | 100 | 34.9M | 20000 | 100% | 45% | 210,196K |
| 3 | 200 | 31M | 40000 | 100% | 45% | 270,960K |
| 4 | 400 | 32.9M | 80000 | 100% | 45% | 364,234K |
| 5 | 1000 | 28.6M | 200000 | 58.84% | 100% | 540,664K |
The performance of 1000-user can also be improved by adding RAM of the monitoring computer.
Test Environment
| 1 | Network | 100M ethernet |
| 2 | Test Client | Intel(R) pentium(R) Dual 1.80+1.80GHz , 1G RAM |
| 3 | Test Monitoring Server | Intel(R) Celeron(R) 2.66GHz, 1G RAM |
| 4 | WFilter Version | WFilter 3.3 |
| 5 | Switch | Tplink TL-SF1008 |
WFilter 3.3 is under alpha testing now. The new version will add "Bandwidth limit", "Url keywords blocking", "Website visit quota" and other exciting features. 1. "Bandwidth limit". You can set bandwidth limit for each computer, or blocking certain internet traffic when internet bandwidth is too high. This feature can help you to manage company bandwidth flexibly. 2. "Url Keywords Blocking", blocking url/webpage by keywords category. You may use this feature to block certain keywords from being searched in search engines. 3. "Website visit quota", by this feature, you are able to set visit time quota for each website category. For example, "news" websites can be limited to "1 hour" for each day.
Some websites, like facebook, youtube, are rather time consumable.
If you do nothing to filter certain websites, your employees may spend several hours a day on web surfing.
So How to block certain websites to save your productivity?
1. Some router/gateway might have the ability to block certain websites.
2. Firewall appliances, like cisco PIX, will also be a good choice.
3. The third, you can choose internet filtering software to do web filter and blocking.
Most employees waste more than an hour on browsing web pages. Even worse, someone will not be able to concentrate on their work during work time.
So, to save productivity, it is necessary for organizations to block certain websites and restrict internet access.
In my opinion, things should be done from several aspects:
1. Only work-related websites are allowed during work time.
2. Destructive websites like violence, adult, shall be blocked always.
3. Downloading websites shall be blocked to save bandwidth if you are suffering from slow internet speed.
For those companies who are very strict with websites browsing, you can implement a website whitelist, by which, only websites in the whitelist can be visited.
More information, please refer to internet blocking and internet monitoring.
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