QoS: WHEN TO CONTACT LUCAS VALLEY CABLE

Plans above Basic have, in addition to higher speed caps, "Quality of Service" (QoS) treatment that optimizes performance.

For you to get the QoS that is associated with your plan, our equipment needs to recognize the "MAC address" of your router (or other device that is connected to your cable modem). If you change or remove your router, your QoS policies will revert to those of the Basic Plan until we re-configure our equipment to recognize that change. You can check our current configuration of your account by logging into the Support Page and checking your "Router MAC" and "IP address" settings. If these fields are blank, or different from those on your router's Status page, you are receiving Basic QoS. For this reason it is important that you do not change, replace, or remove your router without coordinating that change with us first.

Contact support@lucasvalley.net to update your configuration when necessary.

BITS vs. BYTES

When downloading large files over the Internet, your computer may give an indication of the speed of that transfer in Bytes per second. That rate is approximately one tenth the bits per second rate used to measure network speeds (there are eight bits in a Byte, but there are two formatting bits that accompany each Byte).

So if a download is moving at 50 KBps, for example, the equivalent rate in bits per second is about 500 Kbps. Note the difference in the notation -- Bytes use a capital B and bits do not.

What Speed can I Expect on the Internet?

Internet throughput has two components: download and upload. Most people are concerned with download speed because most Internet usage is the acquisition of information, whether that information be text or some kind of multi-media material. Of course, one must to do some uploading in order to navigate to the source of the information and specify what information is needed. Historically, on our system, approximately one byte of information is uploaded for each two bytes of information downloaded.

Factors Affecting Internet Speed

A number of factors affect the speed of an Internet connection. The numbers below refer to the figure at the left.

1. TCP/IP Overhead.: The protocol most used on the Internet is called TCP/IP (Transport Control Protocol/Internet Protocol). TCP/IP embraces many other protocols that handle mail, web casts, and endless special services. While TCP/IP is very efficient, it is not perfect. Network throughputs are measured by the actual bits transferred in one second. For the bits to contain useful data, they must be grouped into "packets," each of which are preceded by several layers of header information that increase the amount of data by about 3%. Transporting the packets requires the acknowledgement of each packet and the resending of any packets that arrive damaged, which adds an additional 10% for DSL and cable modem systems such as ours. The result is about a 13% difference between the raw data rate over the network and the rate that actual data is moved, and this difference is called "overhead."
2. Speed of the distant source of information.: This depends on the (2a) speed of the distant server (which varies depending on the number of simultaneous users accessing) and (2b) the size of its pipeline to the Internet. When one experiences fast downloads from one site but slow download speed at nearby site, one can probably surmise that the second site is suffering a bottleneck due to one or more of those factors. The so-called "denial of service" attack by hackers on a target web site is an example of how a site can be slowed by excessive requests.
3. Speed of the Internet itself.: The Internet is comprised of countless nodes through which data packets find their way between their source and destination. While it is typically capable of providing multiple paths for data to flow around bottlenecks that may materialize at any one particular node, the complexity of traffic over the Internet at any given time is so great that it is impossible to estimate how the overall Internet will perform. The services that provide the Internet backbone are constantly monitoring usage patterns and making needed adjustments, so Internet is always changing. The fact that one can get widely differing throughput (Internet "speed") depending on the point of entry, the point of exit and the time of day is an indication of the impossibility of predicting speed over the Internet itself. Users wishing to measure the speed of their connection are best advised to minimize the influence of this component by selecting a speed measurement service that is connected to the Internet fairly near to our own connection (the San Jose area in our case).; According to a USA Today article on February 8, 2006, the recent popularity of huge downloads (movies, etc.) has caught the Internet off guard. It may take a while for Internet speeds to recover.
4. Speed of the LVC Pipeline.: Lucas Valley Cable connects to the Internet over a very fast fiber-optic cable. However, like all providers of Internet service, that pipeline has fixed limits. Because all of our users share the same pipeline, there are times when the demand to move information through the pipeline approaches its maximum capacity. When that happens, some packets are put into a queue and sent a few milliseconds later. This results in a reduction of Internet speed for some services. To minimize the impact of congestion, we have QoS equipment that prioritizes data packets based on their protocol and the level of service of each user (see see QoS ).
5. Speed of the LVC Cable Modem System.: All cable modems on our system share a single downstream channel, so it is logical that the throughput of any one customer can depend on the activity of neighbors. This fact is cited as a cable weakness by DSL advertisers because that system does not have customers share a common data link. However, one of the great advantages that Lucas Valley Cable enjoys is its small size. The cable modem equipment that we use is designed to serve much larger communities. As a result, our cable modem system is capable of very high throughput and is not a significant factor affecting a given user's speed. The only exception to that is when there are problems on the cable system itself.
6. Your Computer.: In these days of virus, worm, and spyware infections, many computers slow to a crawl because they are running excessive processes in the background, are sending packets out on the Internet without the user's knowledge, or both. This problem is simple to isolate if you have one of our multi-computer plans, because it usually affects only one computer. If you have access to a laptop that is known to be working properly, you can try substituting the laptop for the suspected computer to see if the problem disappears. We strongly advise users to equip all computers with a firewall, anti-spyware, and anti-virus applications and to keep those applications up to date.
7. Your Router.: More than half of our customers have routers that allow Internet access to be shared by several computers. Other computers connected to the router can affect the throughput because of this sharing process. If you are measuring speed, be sure all other computers are off the network.
8. Speed Caps.: Speed caps ensure that no one user monopolizes the service, locking out others. They are last on the list because they only kick in when the speed resulting from the combination of all of the above factors exceeds the cap. When that happens, the cable modem system deliberately slows down data flow until the cap is reached. Speed caps limit the maximum speed of every user, and depend on the Broadband Internet Plan that applies in your case: