Chapter 10:
1a: There are several distinctions between LANs and WANs, however, the most prominent feature separating the two is the geographic aspect, LANs are generally contained locally and maintained within an organization, inside the organizations premises. WANs on the other hand can span large areas which are separated by leased lines outside of the control of the organization.
1b: Rights of way are areas designated by local governments for use in the installation of data lines for private communications companies- aka carriers..
1c: Carriers are private communications corporations who facilitate the transport of data over privately owned data cables- in many cases, their own data cables.
1d: Users have more flexibility over their own LANs as opposed to WANs because all of the components and materials can be managed by the local organization, rather than having to deal with 3rd parties such as carriers and governments.
9a: DSL connections are likely to be less expensive because of the overall cost of installation. Since DLS can use single pair UTP, the speeds are significantly less, in addition the lines are likely already leading to a business.
9b: Most business DSL service speeds are symmetric, in that their upload speeds are very similar to their download speeds.
9c: The speeds of HDSL are toughly 786 kbps both up and down (symmetric) HDSL2 transmits symmetrically at 1.544 Mbps, finally, SHDSL transmits symmetrically between 384 kbps and 2.3 Mbps.
9d: While the book only mentions SLA’s between businesses and carriers, there is likely at some level or another mutual expectation of proper service for residential customers.
9e: Currently the fastest DSL standard is VSDL2, which 100 Mbps symmetrical transmission.
9f: It is difficult to compare VDSL and VDSL2 to traditional DSL due to the fact that carriers are offering the service over fiber, rather than single pair VG UTP.
10a: Asymmetric speed is acceptable in residential DSL because a majority of the transmission bandwidth is spent downloading rather than uploading. The need for download speed far exceeds the need for fast upload speeds.
10b: The benefits of not providing WoS guarantees to residential DSL customers is that they can offer the service period, as there is such a disparity between quality depending on the customer distance from the central hub, it would be difficult to maintain a certain level of service for all customers.
10c: Residential DSL offers simultaneous voice and data service, a splitter and/or filter may be necessary to separate the noise shared between the two services over the same line.
10d: The only equipment a customer needs in the home for DSL service is splitter, single pair voice grade UTP and a DSL modem.
10e: The purpose of the DSL access multiplexer, or DSLAM, is to separate voice and data traffic. It connections tradition voice with the public switched network and links data traffic to the data network.
10f: Initial ADSL speeds were rated at 1.5 Mbps down and 0.5 Mbps up, which today is painfully slow compared to the current 24 Mbps down, and 3.3 Mbps up.
10g: 10f contains the answer to this.
10h: Three factors reduce a user’s actual throughput from the rated speeds. These include the quality of the residential wiring plant, the distance between the customer and the central office, and line noise.
10i: Fiber to the home is attractive because it offers high speeds of up to 100 Mbps.
10j: Generally, fiber to the home requires a carrier grade fiber to be pulled to the actual house. Costs are mitigated by converting entire neighborhoods one at a time.
11a: Cable television companies use a combination of coaxial cable, and in some cases carrier fiber as their transmission media.
11b: Coaxial cable gets its name because it contains two conductions that have the same axis.
11c: The coaxial trunk is the main thick cable branching from the neighborhood splitter, and further branching off into smaller drop cables which
