Happy Birthday to the T1, it is now 50 Years Old !
Are you running your business on 50 Year Old Technology?To Compare Copper vs. Fiber - Let's begin in the street.

T1 and Plain Old Telephone service are in the same copper wire boxes. On the left is a very messy Aerial box. On the right is a ground box. This is nice and clean. As clean as it gets. T1 lines travel from the CO (Central Office) through a series of these boxes. Can you see how easy it is for your wires to get wet in the rain or mistaken for another wires? When Grandma & Grandpa can't hear, these boxes get opened (or remain open).

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Technology Comparison Chart
(See Whitepaper and MP3 on Fiber vs. Copper and Wireless)

Data	Speed	Max	Cost by	Distance	Weather
Service	Expansion	Speed	Distance	Limited	Effected
				(sold as up-to)
ADSL up	_ 128k	500k	NO	YES	YES
down	_ 500k	3 Meg
SDSL	_ 144k	1.5 Meg	NO	YES	YES
Bonded T1	_ 1.5Meg	1.5 per	YES	NO	YES
T3/DS3	_ 8M	45 Meg	YES	NO	YES
HDLC	_ 1 Meg	8 Meg	YES	YES	YES
(Also called New Ethernet over Copper)
Fiber GigE	_ 3M	1 Gigabit	NO	NO	NO
(Also called Fiber Ethernet)

Business Data Services.
DSL - There are several versions of DSL. Anything other kind of DSL is simply a modification of a version. All DSL services are terminated on a DSLAM, Digital Service Line Access Multiplexer. This device usually has more lines connected to it than the amount of Internet bandwidth it has available. Multiplexing congestion is normal during peak usage times.

ADSL is Asymmetrical Digital Subscriber Line This is the most common form of DSL for home and businesses that do not need dependable internet access. It is called Asymmetrical because the down stream speed of data coming down to you is faster than the speed of data up from you. ASDL is distant dependent, so the farther from the Central Office the slower the speed possible. Service is sold as "up-to" as no actual speed is promised.

SDSL is Symmetrical Digital Subscriber Line This is the same Digital Service with the ability to go the same speed up and down. However, like ADSL the speed possible is distant dependent. Like ADSL, service is sold as "up-to" as no actual speed can be promised.

T1 A 50 year old technology called Transmission Level One. In 1958 Bell Labs developed the T1 the same year the Edsel was born. The T1 was originally developed to digitize voice calls in areas where many phone lines were required. This increased the number of calls handled over copper wires, allowing 24 separate voice channels to be carried on fewer copper wires. It is an 8 bit byte oriented protocol. The speed is limited to 1.5 megabits per second in both the up and down direction with a 1% packet loss.

Bonded T1s Multiple T1s added together on the router ends to deliver a faster throughput. Due to multiplexing and linear loss potential allowed Bonded T1s are generally sold as 1.5 megabits per second per T1 with 1% loss per T1. There is no promise of total speed through bonding.

T3 This is equal to 28 T1s multiplexed into a single copper coax cable. Originally used between central offices to switch T1s through multiple central offices, T3s are limited to 45 megabits/second. The more reliable of copper services they are sold in fractions with 1% loss overall

Notes on both T1 and T3 services: They are priced based on distance. The further from the CO the more expensive the service. In addition, every 1,000 feet requires amplifiers along the path to keep the electrical signal at a functional level. As with all copper electrical amplification it is affected by the weather. The amount of loss now allowed by the California Public Utility Commission is 1%.

HDLC is High-bit-rate Digital Link Control. Commonly is used for Ethernet over copper delivery and is very similar T1 technology. It uses copper pairs and electrical signals, but unlike T1s it is not a byte oriented protocol. HDLC is a more efficient method of using 1s and 0s using Cyclic Redundancy Checking, CRC, and bit sequence markers. Using copper, like T1s is distant dependent in price and speed throughput. Various manufacturers use multiple copper pairs to produce data bit rates speeds of 2, 4 or 8 megabits per second. Using copper, like T1s, it is distant dependent in price and speed throughput.

Fiber GigE service is the most reliable service available. Delivered on fiber, packets leave a router to the street at gigabit speed (GigE). The distance a packet travels in the street is several miles. Due to this laser transmission, distance ability amplification along the way is rarely required. In fact, if the distance is short a device is put in place to lower the light signal level. Fiber Internet Center lights its’ own dark fiber as well as utilizing phone company fiber to reach a large number of businesses in California. Fiber Internet Center services are not distant dependent. There are few exceptions to this in areas where special PUC tariffs apply. Generally, a packet loss of less than one percent is due to router software or other limitations. Unlike copper and copper amplifiers, packet loss across the fiber path itself is very rare.