Optical Networks: A Practical Perspective - Part 68 doc

... 12 1.3 .2 Second-Generation Optical Networks 14 1.4 The Optical Layer 16 1.5 Transparency and All -Optical Networks 24 1.6 Optical Packet Switching 26 1.7 Transmission Basics 28 1.7.1 Wavelengths, ... 2 Propagation of Signals in Optical Fiber 49 2. 1 Light Propagation in Optical Fiber 50 2. 1.1 Geometrical Optics Approach 50 2. 1 .2 Wave Theory Approach 55 2. 2 Lo...

Ngày tải lên: 02/07/2014, 12:21

... Note that V decreases with a and A - (nl - n2)/nl. Thus single-mode fibers tend to have small radii and small core-cladding refractive index differences. Typical values are a = 4/zm and A 0.003, ... ' ' ' ' ' ' 1450 1500 1550 Wavelength (nm) L-band v , l , , ~ ~ i 1600 1650 Figure 2.7 The three bands, S-band, C-band, and L-band, based...

Ngày tải lên: 02/07/2014, 12:21

... is that the signaling rate on the channel is lower than the data rate. For example, a 16-level modulation scheme would be able to transmit at a date rate of 40 Gb/s but at a signaling rate of ... z(nT- T) y(nT) - y(nT - T) + z(nT - 2T) y(nT) - y(nT - T) + y(nT - 2T) - z(nT - 3T) y(nT) - y(nT - T) -t- y(nT - 2T) + (-1 )n-ly(T)...

Ngày tải lên: 02/07/2014, 12:21

... peak-to-peak variation of the chromatic dispersion from the average over the span. In Figure 5.33, the peak-to-peak variation was chosen to be small (1.6 ps/nm-km), and thus both the anomalous ... that we studied in this chapter apply to point-to-point links as well as all -optical networks, and we have attempted to con- sider several factors that affect networks more than point-to-point...

Ngày tải lên: 02/07/2014, 12:21

... (LSR). Each packet now carries a label that is associated with a label-switched path. Each LSR maintains a label-forwarding table, which specifies the outgoing link and outgoing label for each ... forwarding (EF) are handled in a separate queue and routed through as quickly as possible. Several additional priority levels of assured forwarding (AF) are also specified. An AF has...

Ngày tải lên: 02/07/2014, 12:21

... efficient algorithms are known for the solution of arbitrary ILPs and MILPs. In fact, a general ILP or MILP is an example of an N P-hard problem [GJ79]. Commercial packages are readily available ... variables are real. It is called an integer linear program (ILP) if all the variables are restricted to take integer values. In our case, some of the variables, for instance, the bij, are...

Ngày tải lên: 02/07/2014, 12:21

... channel-section trace, which is associated between each adjacent pair of regeneration points of the lightpath. Within an all -optical subnet, we can use a optical channel-transparent section trace. ... Figure 9.2 Layers within the optical layer, showing the optical channel-path (OCh-P) layer, optical channel-section layer (OCh-S), optical multiplex section (OMS) layer, and...

Ngày tải lên: 02/07/2014, 12:21

... also been adopted for standardization by the ITU. 9.6.3 Adaptation Management Adaptation management is the function of taking the client signals and converting them to a form that can be used ... to be capable of supporting a variety of bit rates as well. An important enabler for this purpose is a programmable clock data recovery chip that can be set to work at a variety of bit...

Ngày tải lên: 02/07/2014, 12:21

... support aggregate traffic capacities higher than the transmission rate. UPSRs are popular topologies in lower-speed local exchange and access net- works, particularly where the traffic is primarily ... while many long-haul carriers have deployed BLSR/4s. BLSR/4s can handle more failures than BLSR/2s. For example, a BLSR/4 can simultaneously handle one transmitter failure on each span in...

Ngày tải lên: 02/07/2014, 12:21

... centralized and operated rather slowly, taking minutes to hours to restore traffic after a failure. Also the protection was complex to manage, and there were no applicable standards. After ... others are turned on, creating a bus. (b) After a failure, the currently inactive amplifiers are turned on and an amplifier pair adjacent to the failure is turned off to bring up the alternate...

Ngày tải lên: 02/07/2014, 12:21

... routes that it can take, all consisting of multiple links and routing nodes. If the route chosen for this packet is 1 -A- B-D-F-6, this packet traverses the links I -A, A- B, B-D, D-F, and F-6. ... electrical domain. The routing and forwarding functions, in particular, fit into this category. Most PPS proposals to date assume that the packet header is transmitted separately from the...

Ngày tải lên: 02/07/2014, 12:21

... followed by a packet burst. Typically the header is transmitted at a lower speed on an out-of-band control channel, although most proposals assume an out-of-band control channel. An intermediate node ... (c, aoal a~ -l) to a node ((c + 1) modk, ala2 a~ -l.), where 9 ~{0,1 A- l}. 12.4 Buffering 645 architectures have been proposed that trade off these parameters against each o...

Ngày tải lên: 02/07/2014, 12:21

... routers and large optical crossconnects (OXCs). In general the trend to date has been that the total capacity that can be switched by a top-of-the-line router is much smaller than the total switching ... connecting patch cables between back-to-back WDM terminals within the optical layer. This approach is the lowest-cost option, as all passthrough traffic is handled without additiona...

Ngày tải lên: 02/07/2014, 13:20

... increases in the number of wavelengths. Today's state-of-the-art long-haul systems carry about 100 channels at 10 Gb/s each and have regenerator spacings of 400 to 600 km. The ultra-long-haul ... it makes sense for them to deploy WDM at OC-192 rates, and that is what they have done. As we have mentioned earlier, systems operating in the C-band as well as in the L-band are now availa...

Ngày tải lên: 02/07/2014, 13:20

... G.957. Optical interfaces for equipment and systems related to SDH. G.959. Optical networking physical layer interfaces. G.983. Broadband optical access systems based on passive optical networks ... Characteristics of a nonzero-dispersion-shifted single-mode optical fiber cable. SDH (Synchronous Digital Hierarchy) G.691. Optical interfaces for single-channel STM-64, STM-25...

Ngày tải lên: 02/07/2014, 13:20