Monday, March 15, 2010

Tips For Optimizing Your WAN (Wide Area Network)

So you're looking to optimize your WAN for your business and need to know what your options are. Upgrading your bandwidth to MPLS or Ethernet isn't necessarily the solution. Bandwidth utilization is the key for optimizing your WAN.

Packeteer, Riverbed and Juniper are WAN optimization systems that do an excellent job with latency, especially if CIFS WAN-unaware situations such as opening, copying and modifying files using Windows are the main problem.

To identify the delay, you need to find the path your IP packets take. A satellite connection versus a landline connection (such as earthbound wireless, land or underwater fibre) can be the source of the latency problem. Check with your service provider to get a service level agreement to guarantee the quality parameters you want concerning packet loss, delay and jitter.

It's very important to not buy or install any new network system before identifying existing delays.

Once the latency issue is identified, a valid solution for optimizing your WAN is to purchase a WAN-accelerator from a vendor that offers such a product. The amount of traffic your WAN uses will also determine which vendor you will choose for this product. For example, if your business uses such programs as Citrix and SAP, then a traffic-prioritizing WAN accelerator such as Packeteer or Ipanema would be the best solution. But if your business uses more file-oriented applications, your best option would be to purchase a data reduction accelerator like Riverbed, Juniper Citrix and Cisco. Riverbed is by far the best solution.

While optimization systems effect only TCP flows, latency issues with UDP flows (VoIP) can't be resolved since real-time traffic is naturally subject to delays. Citrix WANScaler, Cisco WAAS, Juniper, Riverbed and Expand as well as other vendors sell systems for optimizing generic TCP flows which would meet the needs of your business.

As a word of caution, all the vendors hide the effects of latency. WAN optimization solutions act like an invisible TCP proxy, simultaneously spoofing both the server's IP address to the client and the client's IP address to the server. The TCP ACK messages are sent locally, speeding up the delivery of the ACK message and avoiding latency effects. TCP connections and throughput are subject to latency when the ACK messages are returned.

Vendors also hide the effects of latency by utilizing the entire WAN bandwidth link for implementing selective ACKs and large initial flow control windows. Compression mechanisms, layer 7 optimizations (mostly CIFS file-sharing as well as HTTP-based compression), embedded QoS are used for artificially increasing bandwidth not in use. This is known as "WAN optimization".
w

Monday, March 1, 2010

Reducing Costs - WAN Acceleration

According to Gartner, WAN optimization is about improving the performance of business applications over WAN connections. Most networks carry a variety of types of traffic, of differing characteristics and importance.

Many organizations are striving to manage this traffic to optimize the response times of critical applications and reduce costs, given that bandwidth continues to represent a significant proportion of operating expenditure for wide-area data networks.

The primary function of a Web Optimization Controller (WOC) is to improve the response times of business-critical applications over WAN links, but they can also help to maximize return on the investment in WAN bandwidth, and sometimes avoid the need for costly bandwidth upgrades. To achieve these objectives, WOCs use a combination of techniques, including:

- Ensuring fair access for mission-critical applications during periods of congestion by prioritizing business critical traffic, through QoS policing and traffic shaping, for example

- Minimizing the effects of network latency using methods like protocol- and application-specific optimization

- Reducing the bandwidth required to transfer WAN traffic by compressing it, for example.

Click here to read more from Gartner about the WAN optimization market.

The WOC market is maturing rapidly, but it is still dynamic with a high level of vendor innovation.This has led to different vendors offering different combinations of features. In order to ensure that the most effective solution is put in place, providing the best overall return on investment, a detailed analysis should first be undertaken. This will establish:

- The real bandwidth you are achieving

- The real usage of that bandwidth

- Applications and services running on your network and the protocols they use

Also conduct a detailed analysis of your network traffic to identify specific problems, for example, excessive latency, bandwidth over subscription or lack of prioritization for certain types of traffic.

Wednesday, February 17, 2010

The Importance of Keeping Up With WAN Optimization Techniques

To understand the different techniques used by appliances offering WAN optimization, it's important to first define exactly what exactly a 'WAN' is. WAN stands for 'wide area network' and refers to any network that covers a very large geographic area. By contrast, a LAN, or local area network, refers to networks that provide internal communication in a home or small office. The internet as a whole can be defined as a WAN and is obviously a public network, while an example of a private WAN could be a corporation with offices in San Francisco, San Jose, Austin, Boston, and New York. Each individual office would have a LAN set up internally, but could also use DSL or MPLS connections to form a WAN to share information between offices.

There are a number of performance-related issues that typically occur with WANs, which has led to the development of various WAN optimization techniques. These issues can include redundant transmissions, 'chatty' protocols, and packet delivery issues. Some of the common techniques used to achieve WAN optimization include: Bandwidth Management; Caching; and Protocol Optimization. Multiple vendors offer WAN optimization appliances that use a number of these techniques to process the IP traffic traveling between the sites over the company's WAN. Not every solution uses the same techniques, thus the benefits can vary, which is important to understand when researching a vendor or supplier.

Bandwidth Management allows applications to have set limits and minimums with regard to how much bandwidth they use. For example, this technique would allow you to put a limit on the amount of bandwidth an especially avaricious application can use. Conversely, bandwidth management can ensure that less-used applications always have a guaranteed amount of bandwidth allocated to them.

Caching allows several copies of important files, especially larger ones, to be stored in multiple locations. This prevents users from having to download files as large as 20MB or 100MB across a WAN connection every time they need to view or make edits to it. Additionally, whenever modifications are made to one of these cached files, the network doesn't have to transmit the entire updated file to every one of its multiple locations. One the portions of the file that have been edited are sent.

Communication protocols for digital computer network communication have features intended to ensure reliable interchange of data over an imperfect communication channel. It is basically a way of following certain rules so that a system works properly. Protocol optimization restricts the amount of electronic chit-chat that occurs between sites when communication protocols send their necessary back and forth confirmation messages.

The implementation of these various techniques by using WAN optimization appliances has been said to reduce the usage of bandwidth by as much as 50-95% between offices communicating over the WAN. For many companies this means thousands of dollars of savings, particularly when costly solutions like multiple MPLS networks are being to ensure network reliability. For others, the value of WAN optimization is that global collaboration allows the company to undertake tasks that it previously couldn't. Regardless of the benefit or the need, understanding the latest in WAN Optimization techniques can have a substantial benefit on the performance of a modern corporation.

Charles Hughes is author of this article on WAN Optimization.

Monday, February 1, 2010

When Should You Add More Bandwidth To Your Business Network (eg WAN)?

Many businesses ask this question. It's common ..... so don't feel alone.

Is there a general rule of thumb, a percentage of bandwidth usage, that is an indicator that it is time to lease more bandwidth?

The true answer here is, "It depends".

Of course you need to know how many users you have ..... and what they're using the network for (e.g. CAD, Multi-media applications, sharing large data files, medical imagery, etc.). That's a factor in your ultimate decision obviously. As is what is the operation, are users on one side and servers on the other, are servers and users on both sides, how many points? Plus .... are either of those categories (number of users, applications) going to grow in the near future.

If growth of users and/or applications is in the distant future ..... you have more room to plan and maybe go with a gradual solution in the interim. In this case you may be able to go with a bonded T1 or burstable DS3 bandwidth rather than a full DS3 or OC3 bandwidth.

Before you can make a real decision on increasing your bandwidth though (thus increasing your expenses) the first step is to log/record your bandwidth usage patterns for a specific period of time - I'd say at least a month (30 day period). This will create a decent benchmark on where you stand in regards to your bandwidth needs.

Ignore occasional spikes -- spikes will happen, this is a reality of networking. However if you have sustained spikes lasting for several minutes at a time and this occurs at least once every day that is a hint of a larger problem.

(If that happened I'd note the time of day such spiking occurs, then correlate the times if they match up to any specific task the company is doing during that time period each day).

However, as a general rule ..... look at the bandwidth usage throughout the day. If the average usage is at 50% then start to talk about increasing the bandwidth. If it's at 70%, you will start seeing major trouble, don't just talk about increasing bandwidth then, DO IT.

If you want to be a bit more lenient rather than conservative on your benchmarks ..... get excited about increasing bandwidth when you consistently see usage at 75% bandwidth, when it hits 85% there is no debate, no talking ..... just order more bandwidth.

But, remember to base your decision on the average usage ..... not the spikes that may occur during the day. Again, spikes will happen no matter what your bandwidth is.

Here's another tip (or two) .......

Much of the time bandwidth is not the problem, but the amount of clutter and the lack of optimization at the machine level.

So ..... on every computer on the network do the following:

First, delete any temporary files (even temporary system files) in the c:\windows\temp directory and in their profile under local settings.

Second, get rid of any unused applications.

Third, ensure that the swap file is optimized.

Fourth, Stick more memory in the system if possible.

Last, Defrag the hard drive!

Following the above you should be able to reclaim some speed. If speed is your main issue (it isn't always).

Also .... if you get your files of a network server don't forget to optimize that as well. But the first rule we tell users is do not work off server copies if you can help it.

Now, if after going through all of the above you still decide you do need more bandwidth ..... you can get free assistance to find the right solution (at the best price too) at DS3-Bandwidth.com.

Michael is the owner of FreedomFire Communications....including DS3-Bandwidth.com and Business-VoIP-Solution.com. Michael also authors Broadband Nation where you're always welcome to drop in and catch up on the latest BroadBand news, tips, insights, and ramblings for the masses.

Friday, January 15, 2010

LAN & WAN - Does a Letter Really Change the Meaning of the Word?

Of course! Particularly when that one letter is a part of an acronym. As with the topic at hand, the difference between LAN and WAN lies deeper than the obvious spelling and phonetic. In many respects, there exist no single distinction between local area network (LAN) and wide area network (WAN). But there are, in reality, several differences that may well distinguish LAN from WAN.

The points to be considered are the following: geographic, connections, topology, usage, reliability and of course, the cost. We will first touch the comparison with regard to the geographic scope.

Scope

Given what LAN and WAN stand for, one can easily identify an immediate difference: the scope of WAN is clearly vast as compared to that of LAN. The former possesses networks that could spread across city to city, sometimes even on a broader scope. With that said, LAN may be deemed as an undersized version of a WAN and is usually limited to a single edifice or a residential house. So if you connect all the LANs then you may have just developed a WAN---a small scale WAN, that is.

Connections

On a local area network, Ethernet is the established standard for connecting computers or workstations. In here, wires and cables are but permanent. This arrangement allows interconnectivity among separate local area networks. As for the wide area networks, they almost always depend on common carriers or a system where they utilize or hire service providers to be able to interconnect.

With the issue on speed, LAN is approximately ten times faster than WAN. One cannot impartially compare the LAN's speed reaching 10 gigabits per second to a WAN's fastest speed of 155 megabits per second. (Talk about no competition.)

Network Topology

As shown in the previous paragraphs, WANs and LANs are configured differently. More often than not, the latter is inclined to be a peer-to-peer networking where one computer may share (and sometimes access) data and applications in other computer units within the network. While WAN operates in a client-to-server level and most, if not all, data originates from a central computer or server.

Usage

Continuing the discussion, the peer-to-peer sharing is commonly used to access files, as well as printers, scanners and other peripherals. The usage is somewhat controlled and restricted among a few groups of people. These users have their own passwords that will allow them to access a particular data (not the entire folder or drive). An administrator may also be present. In a WAN, it is not really the sharing of peripherals or whatnot, it stresses more on communications.

Reliability

LAN boasts a higher reliability rate because when one computer fails, all other will continue to operate. In WAN, this is not the scenario. When a unit falters in a WAN, most probably the rest will fail to function as well.

Cost

With the extent of WAN's reach, obviously this costs a lot. Not to mention the need for field experts like engineers to install and maintain all their machines. Sometimes, WAN also necessitates satellite links; yet another reason for its high set-up cost. Local area network, though housed in a single building, will prove to be more cost efficient.

So, in simple equation, WAN=vast reach=costly while LAN=limited extent=cost efficient.

Finally, to answer question posted above (yet again), there is a yawning gap between the WAN and the LAN.

Benedict Yossarian is specialises in internet marketing. Benedict recommends Comm store for networking hardware and Cat5 Cable. For IT training Benedict recommends New Horizons Learning Centres

Friday, January 1, 2010

How Do You Determine the Right Wide Area Network (WAN) Architecture For a Computer Network?

One of the most complicated decisions to make for an IT department concerns the architecture for a multi-site voice/data network. Should the network be based on simple T1 point-to-point bandwidth circuits? How about burstable DS3 bandwidth or maybe a single OC3 bandwidth cloud? No matter the bandwidth chosen .... the most efficient design should base the communication backbone on a MPLS configuration (Multi-Protocol Label Switching).

To get there, first and foremost in deciding about the WAN architecture of any organization communication network you must determine ....

- How many locations you would like to connect?

- Architecture - hub and spoke or mesh architecture?

- What applications would be run on this network .... Voice, Video, Data, all of the above?

- Precisely which applications will be run in case of Data?

- What will be the % each will take up of your QoS, the total of all three should be 100%?

- Voice is the premium level QoS and hence the most expensive as it is a real time communication, followed by video and then data.

- How many users precisely will be using the network at a given point of time at each location?

- What will be the concurrency factor? Are you are looking for 100% concurrency or you can manage with lesser concurrency?

- What is the scope of scalability at each location and hub location?

- Will the access to internet also be given to users?

- Internet at a central location can help you in implementing and enforcing various security policies of your organization.

- Do you want to give access to the network resources to a mobile user?

The answer to all these questions will help in arriving at the MPLS bandwidth required at each hub and spoke location.

Honestly speaking no organization should ideally try to do this calculation themselves. Instead they can hire a consultant or a telecom service provider to do this activity as they are experts in designing this solution. With their help you can easily decide upon the bandwidth for each location, select suitable router, make redundancy plans, routing the traffic on Atlantic or pacific routes, blah blah.

For help walking through the analysis .... and determining the best solution .... take advantage of the free help at DS3-Bandwidth.com.

Ideally I also recommend to give the freedom of providing and managing the routers at each location to the Telecom service provider. Then it becomes a managed solution and the service provider can easily monitor your network in the event of an outage. They then can remotely login into the routers and manage your complete network giving you higher uptimes and SLAs.

In the end .... take a deep breath and work through the steps above, also helps to increase SharePoint Performance. Following this simple game plan will get you to the right decision for your organizations network architecture.