Posts Tagged ‘vpn’

Firewalls, Switches, Routers and VPN – Provide High Speed Network Communication!

April 26th, 2012 No comments

A switch is a hardware device that links the data where the Ethernet protocol works.  The switch is using the table to distinguish where to send all future frames that it receives. In technological term this tables is known as CAM table which is used for the bridge forwarding table. If a switch receives a frame with a destination then table floods that frame to all switch ports. It also put the Mac address in the table when it usually receives a frame. As we know switch is a high speed multiport bridge and most routers can also function as bridges.

The example of the SPI hardware firewall is the Cisco PIX firewall. It is the dedicated appliance as well as it looks like the Cisco router. The SPI firewall is stateful as it understands different states of TCP (the transmission control protocol). It knows what comes & what it goes & keeps the track of that all. Therefore, in case, the packet tried and come in however it was not requested, firewall knows that & drops that. Here is what we learned:

  • Routers work in Layer 3 & route IP packets between the networks.
  • Routers are been used to connect the LAN to WAN (like small network to Internet) however they will as well get used to connect the segments of large LAN, which is subnetted in the smaller segments.
  • Routers route the packets that are based on the information in IP routing table. You may see the table with show ip route command on the Cisco router.
  • Switches work in Layer 2 as well as switch Ethernet frames and switches connect the multiple devices on the local area network.
  • Switches keep the table of the Ethernet MAC addresses named the CAM Table or Bridge forwarding table. You may also see the table with show mac-address-table command at the Cisco switch.
  • Firewalls work in Layers 3 & 4 however some will work at the higher layers.


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Firewalls, Switches, Routers and VPN – Offering Quality Network Communication!

April 25th, 2012 No comments

These days, every types of business are hugely depending on the quality of its communication network. Information technology is much required for the business and your business will definitely struggle without the expertise of networking solution. Networking solution in relation to firewall, switches, router and VPN are the most respected communication solution in the business communication world. There is no further option than Cisco, when it comes to communications network. You will need expert assistance in the configuration of your system, once the right system has been determined. You can’t just guess what the right configuration for your company is. While it gets the response, it puts MAC address in a table so it will not need to flood the next time.

Router gets this, replaces source address, changes destination address to original address as well as sends this packet back to original sender. It is the complex topic, which we can spend the whole article covering thus this is just meant to give most basic understanding how it actually works. In order, to show routing table on a router, make use of show ip route command. So, here is the example of what the routing table looks very much like on the router:


The switch is the hardware device , which works at the Layer 2 of OSI model – the data link. Data link layer is actually where Ethernet protocol works. The switch switches the Ethernet frames just by keeping the table of what the MAC addresses are seen on what of the switch port. Switch makes use of the table to determine where you can send all the future frames, which it gets. In the Cisco terminology, table is named CAM table (the content addressable memory). Generally, proper term for the table is bridge forwarding table. In case, the switch gets the frame with destination MAC address it will not have in he table, it also floods frame to all the switch ports.

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Firewalls, Switches, Routers and VPN – Improving Capabilities of Every Device!

April 23rd, 2012 No comments

Business devices have become more and more unite over time just like home devices. Network administrators in a business network are always comfortable with separate devices because they like to be cut off problems to a certain device to know the performance capabilities of every device. If you are using integrated router, firewall, switches all into one device then understanding the performance capabilities of every device can be get complicated. You should remember that these integrated devices won’t work well for medium or large size business because they don’t offer all the features required. The firewall, switches, routers and VPN has all the features that you require.

In an event that destination is not at all listed in routing table, router can either send a packet to the default router (in case, it has one) and drop packet. The routers are generally used to connect the local area network to the wide area network (LAN to WAN) but will as well get used to segment the large local area (LAN’s). The routers stop broadcasts and one more method to save this is routers form the broadcast domain. Thus, in case, the network is to be deluged by the IP broadcasts, you have to subnet the network in 2 and more smaller networks.

These networks will get connected by the router and this router will not allow the broadcast traffic to flow it between the subnets. The routers make use of routing dynamic protocols such as RIP, OSPF, and BGP to learn the routes from some other routers. The router will as well make use of static routes, which are entered by administrator. The routers replace Ethernet MAC address of source device with the own MAC address while they send the packet out the interface. While response to this packet comes back, new source of a packet is now sending response to destination of a router.

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Firewalls, Switches, Routers and VPN – Collect More

December 1st, 2011 No comments

It’s the 21st century, and numbers of people are looking for the secure online way to start their business. If you want to start your business, then you need to select the best networking device from these firewalls, switches, routers and VPN. You can use these networking systems in a combination due to their different functionality. Before using these networking systems, you need to collect more information about these networking systems from online.

These genres of networking systems are used to protect and secure local network connection through the Internet protocol. It is the best option for you to get more information that can be used for installing these networking systems for home networking business.

Security is assured by advanced proven, SPI, stateful packet inspection, feature. For the wireless connections, that features fast 802.11n the wireless access point. For the support of the VoIP voice, for the video and the data traffic, Quality of the Service support is given. Cisco FindIT Discovery Utility makes that simple to find the network attached devices. One more management feature, inter VLAN routing office network in the components, which generally are not available between one another still they are routed to connect.

In case, you are searching for the Cisco home router, this is the overkill, however for the home office, and small business use, VLAN routing feature can be invaluable.

Cisco Business RV042 WAN VPN Router

RV042 is the advanced internet network solution the small business, and home office. That features the dual Internet ports on 10/100 4Port VPN Router allow you connect the second internet line like the backup to minimize internet downtimes. In the same way, you may as well let router balance the office’s requirements in them for the maximum internet access efficiency. They can as well be making use of it as a main Quickbooks server and server for other accounting program. I was thinking I will want the Quad i5 and Xeon with the 8GB of RAM.

Categories: General Tags: , ,

Firewalls, Switches, Routers and VPN

November 25th, 2011 4 comments

Are you learning about how the business uses the networking systems? Well, you may be surprising why there is much essentiality on the difference between a switch, routers, firewall, and VPN networking systems. These four networking systems are basically designed to use for the Internet protocol. Keep in mind that these genres of networking systems are having different functionalities.

So, you need to understand the functionality and utilization process of these networking systems. Now, these networking systems are becoming essential for numbers of business. So, it is the perfect option for you to download the trail version of these networking systems online. You can also collect some information about these switch, routers, firewall, and VPN networking systems from previous users.

I am not saying this is not done and you may buy the big as well as expensive, chassis based, the Cisco 6500 series switch & have all the functions on various blades of switch. This is good for the larger business with the group of administrators however to the medium size business as well as single network administrator, lots of times, it is the scary thought. Remember that for the medium or else large size business, the integrated home devices will not work as they will not give all these features needed. Standalone routers, firewalls and switches, have a lot of more features than the integrated devices do. However, what is difference between the devices anyway? Let us now cover three most famous devices.


The router is the hardware device as well as has function of the routing packets between the networks. The router works at the Layer 3 of OSI model –Network Layer. It is a layer that IP protocol works. Most of the routers now are the IP routers, which examine source as well as destination IP addresses of every packet, look up destination of packet in router’s IP routing table, as well as route, which packet on the way.

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Firewalls, Switches, Routers and VPN – It’s All About Selecting the Best Networking Device!

September 21st, 2011 No comments

This time almost everyone wants to bring more customers’ attraction for their business. It can be possible through a secure networking device. However, selecting one of the best networking business is a risky job. So, you need to look for these networking systems like firewalls, switches, routers and VPN through which you can easily start your business.

There are so many users using these genres of networking systems for their business. It is the right option for you to get one of the best networking systems from online media. Let’s look for these networking systems like switches and routers and their function which are briefly discussed at the online media.

Cisco RV042 features six fast Ethernet ports and it supports around 50 separate simultaneous VPN, the Virtual Private Network for the telecommuters & branch offices connections. Cisco VPN software also includes the built in firewall & optional viruses, spam, as well as malware protection, which can help to keep the business safe.

That received actually solid customer reviews in Amazon where you may order at the discount. EtherFast Cable or DSL Firewall Router with the 4 Port Switch or VPN Endpoint is a perfect solution to connect the group of the PCs, like Small Office or Home Office, to the high speed broadband connection or 10/100 Ethernet backbone.

So, everything is upgraded to the Gigabit, probably the couple eight ports and three or so five port switches unless I would like to add more of drops to the rooms. Any suggestions on 5 & 8 port Gigabit switches? As for server, they are using that mostry as the file server, however will need RAID 0+1 on that.

I am planning on running the Server 2008 Foundation and maybe Win7 Pro 64 on it as they may not have to use that as the domain server – they are staying in the workgroup. What are pros and cons of the Server 2008 Foundation and Win 7 Pro? They will need a server to stay the ftp server for the clients for sending them the large files.

Categories: General Tags: , ,

VPNC for Ubuntu!

October 20th, 2009 1 comment

People coming from the Windows world are used to using Cisco VPN client to login to their corporate network.  So when they make the transition over to Ubuntu, they’re somewhat puzzled at the complexity of getting Cisco VPN client working.

It’s obviously not as straightforward as it is on Windows platform but there also has been cases of kernel panics using the Cisco VPN client on Linux.

For those who are looking for an alternative, I’ve got good news.  I came across VPNC recently and it only took me a few minutes to get it installed, configured and get connected to my job’s corporate network.

Supported Platforms:

  • Linux (i386/ppc/zaurus tested)
  • NetBSD (i386 tested)
  • FreeBSD (CURRENT of 23.11.2003 tested)
  • OpenBSD (CURRENT of 18.04.2004 tested)
  • DragonFly BSD
  • Darwin / Mac OS X
  • Solaris (7 works, 9 only with –natt-mode forced)
  • Windows / Cygwin

As you can see it supports more than just Linux but I haven’t yet tested on any other in the above list to make sure.

Quick Setup:

$ sudo apt-get install vpnc
Convert your existing PCF file (if you have any) to vpnc recognized format using this perl script:
$ wget
$ chmod +x pfc2vpnc
$ ./pcf2vpnc orig.pcf vpnc.conf
$ sudo vpnc vpnc.conf

That’s it!  Five easy steps to install, configure and connect to your network.  If you have Kubuntu, you can install kvpnc which by default allows you to use the original PCF file for configuration, so no need to convert here.  I haven’t tested this myself so I can’t say for sure it works.

Go ahead, give it a try.  Read the doc that comes with the source pkg to setup a configuration from scratch.

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