Good network security practices

     Since the rise in popularity of the Internet, we have started to use our computers for a much wider range of tasks than ever before. At home, we buy our groceries, do our banking, buy birthday presents, send communications via email, write our life story on social networking sites; at work, our businesses provide e-commerce via websites, staff send and recieve emails, phonecalls and video conferencing are done through the network using IP based servcices; all of this is done online and it would present a serious security threat if it wasn't for the fact we have various security measures at our disposal. I would like to cover some basic examples of how network security helps to keep us safe online, both at home and in the workplace.

     Any computer network used for business should employ good network security practices in order to keep free from attacks by hackers. There are a number of ways a hacker can hurt your business:

Denial Of Service

     A denial of service attack is used to make your network, or more precisely your website, unavailable to potential users; they do this by flooding the web server with so many requests for information that it uses up all the resources of the web server, which either makes the web server crash, or slow down so much that it can't handle requests from the websites' intended users, your customers.

BlackHat Hacking
     There are people called hackers with enough technical knowledge to be able to penetrate insecure networks with the intent of doing damage to the devices attached on the network and costing the company as much money as possible. Typical damage would involve changing the configuration of network devices such as servers and routers so that earnings where productivity is drastically reduced. Even worse, a hacker can gain access to sensitive information such as credit card details or client/patient records, they can even take control of your network based phone system and make expensive long distance calls at your expense. The damage done can cost your company thousands of pounds, if not more, over the space of a weekend alone.
At home, a hacker has less scope to do damage, but if you keep sensitive information on your PC, like credit card details or scanned images of important documents such as passports and driving licenses, it's clear to see that a hacker can cause you all sorts of grief.

There are a number of technologies and devices that can help keep your network safe:

Firewall
     A firewall uses a set of rules to allow or deny access to a network; typically a firewall lives inside of a router. This router is likely to be the peiece of hardware that sits on the edge of your network and provides access to the Internet. The set of rules are based on opening and closing ports relating to protocols; if the network users don't use a certain protocol, then the router will keep that port closed. 

Access Control Lists
     An access control list is very much like a firewall; it filters traffic based on a number of metrics contained within an IP packet. The Access Control List (ACL) will be configured to check each packets' source and destination IP address, also the source and destination port number. The network administrator will write the ACL, specifying which range of IP addresses can talk to which other range of IP addresses and which protocols they can use when communicating. This makes it very hard for a hacker to gain access around a network, where each router is doing its best to block unauthorised access.

Encryption
     Encryption is simple; an algorithm is used to turn meaningful information into a format that makes no sense and can only be decrypted by someone with access to the specific algorithm. Whenever sending sensitive information across the internet, it's advisable to send it using high levels of encryption.

WEP / WPA
     Nowadays, everyone has got a wireless network at home, allowing them to access the Internet using their laptop in any room. Protecting your wireless network is a must, otherwise anyone geographically close to you can connect to your network; this is a hackers paradise. Research has shown that WPA and the new version, WPA2, are far more secure than WEP. So when you're next setting up your wireless home router, make sure your security is set to WPA2.
     Simply following the aforementioned advice will stand you in good stead, your computer networks and information will be more secure. 

By: Miragetek

the network becomes unavailable; this can take a long time to fix, which translates to a loss of