Routing and Switching: Time of Convergence?

Rating:
Summary: Fundamental, full of tips
Review: Excellent overview of bridging, switching (both in LANs and WANs), and routing. Covers extensively all IP routing issues but also describes how non-IP networks get routed. Handbook for anyone who wishes to know what made switching and routing come "closer": faster and more efficient as in multilayer switching, label switching (MPLS), and optical switching.

Rating:
Summary: Good technical reference, well written. Buy it!
Review: Excellent. Well written, well structured and comprehensive. Breadth of coverage necessarily means less depth on any given subject, but good references allow in-depth follow up. All in all, easy to read and very insightful.

Rating:
Summary: Good book, worth the read
Review: I am a Beng Electronic engineer Final Year student doing my final year project on routing efficiencies, investigating packet arrival times using different routing protocols. I have so far found this book extremely beneficial, which explains a lot of the terminology and techniques in the routing world in great detail. For me its not a book to read from back to back, but one that I found very handy to have near by when working along with my project.

Rating:
Summary: Great Combination: Lots Of Detail, Easy To Read
Review: I bought this book on Brian Dennis' recommendation, and I've been very happy with my purchase. The book goes into a tremendous amount of detail on various bridging techniques and routing protocols, but it's quite easy to read and very enjoyable. Excellent work.

Chris Bryant
CCIE #12933

Rating:
Summary: Great Combination: Lots Of Detail, Easy To Read
Review: I bought this book on Brian Dennis' recommendation, and I've been very happy with my purchase. The book goes into a tremendous amount of detail on various bridging techniques and routing protocols, but it's quite easy to read and very enjoyable. Excellent work.

Chris Bryant
CCIE #12933

Rating:
Summary: Excellent Networking Reference
Review: I found the book "Routing and Switching:Time of Convergence" to be an excellent read. The author covers the topic very thoroughly without getting bogged down in the complexities of the algorithms. I very much like the highlighted boxes called "Standards Watch" and the comprehensive Appendix section.

The book is a perfect cover-to-cover read for those readers who are new to the subject. The author introduces all the important layers of networking before tackling the core subjects of bridging, switching and routing. The last section on QoS, MPLS and Optical switching are especially good and should leave the reader with a good grounding in these new technologies.

For the experienced network design engineer, the book makes a valuable reference. I found myself recalling concepts and standards that I had forgotten in the last few years. I also liked that it is up to date with current topics like wireless LANs and L4-L7 switching. Overall a great reference and a welcome addition to my extensive library of networking books.

Rating:
Summary: Punny Title, Good Read
Review: Puzmanova says the main aim in her book is to show what's behind "the evolution in network interconnection, and give some clue as to where industry developments and standardization efforts are headed: to gain performance by avoiding unnecessary processing in the internetworking device itself, whether router or switch."

Part I is on the principles of network interconnection. This is an overview of the layering principles in building and operating networks. Puzmanova's enthusiasm comes out here as she talks about how she became fascinated in the relaying (routing) principles observed in each layer. She peeled the OSI onion from the outside in, looking at the network from the top layers down. The relaying principles at each layer cover pretty much all the widespread LAN (802.3, Token Ring, FDDI) and WAN (X.25, ISDN, Frame Relay, ATM and SONET) technologies. Then she covers network management and remote monitoring, as well as the principles of network interconnection. At this section she addresses a key question: What is the difference between a router and a switch? After all, switches route, and routers switch. The difference is in the architecture. A switch architecture provides additional forwarding capacity as ports are added. A router typically has a single forwarding engine and additional ports still share the capacity of this single engine. Interestingly, this is somewhat analogous to the difference between shared and switched media, seen in the evolution from hubs to switches. With hubs (as with routers), users share the capacity; with switched media, the capacity is dedicated to all the users.

Part II is very brief and talks about bridging, essentially a precursor to switching. It talks about transparent bridging which is used for Ethernet and source route bridging for Token Ring. The difficulty in creating hybrids for these two is discussed, and indeed there usually has to be some kind of routing function. The important thing with transparent bridging (which has pretty much won the day by the way - forget about Token Ring at this stage) is the prevention of loops through the spanning tree protocol.

Part III deals with switching principles and architectures, including circuit switching, packet switching, and cell switching. Switches have pretty much the same functionality as bridges, breaking up collision domains and sharing a broadcast domain, but with greater port capacity and most of the functionality in the hardware. Virtual LANs (or VLANs) are a way to break up broadcast domains at Layer 2. WAN switches also do cell switching for ATM. The developments in switch fabrics and congestion management define where some convergence in routing and switching is taking place-in multilayer switches (Layer 2 and 3). This has also led to some high speed routers and switches.

Part IV, Routing, is what seems to fascinate Puzmanova the most. All routing has become Routing IP - other routed protocols like IPX and AppleTalk are fading away and more or less don't matter any more. This is good, because routing protocols are complicated enough. Older distance vector protocols (like RIP and IGRP) which use direction and hops and provide the whole routing table in updates, have given way (thankfully) to link state protocols (like OSPF and ISIS); the latter are tougher to administer but bring rapid convergence and all routers know of a topology change, whether it's due to a broken link or an added device, in very short order. Knowledge of routing protocols and their behaviors in different scenarios is the key to the highway for network administrators. Especially important is how different protocols play with each other, in terms of how they coexist, how the filter traffic or redistribute routes into one another, or how they tunnel (wrap packets from) one protocol into another. Routing protocols have extra intelligence but these smarts are processed and take up cycles, and anything that can be done to limit the overhead, by choosing a lighter weight protocol, by redistributing routes, or by using a dial-up link as a backup, is potentially helpful to the performance or the scalability of the network. Part IV also talks about the architecture of routers, in terms of their internal switching fabrics and switching processes. Then it discusses how the highest performance can be achieved with advanced mechanisms that distribute the effort among different devices - the foremost example is label switching or label swapping as used in MPLS, which is essentially a protocol that operates at both Layers 2 and 3, and which helps a network combine the speed of switching with the scalability of routing. This provides another example of the convergence that the book's title implies.

Part V deals with hot topics of the day: speeding things up with QoS and high performance, and optical networking. It also goes into a lot more detail on MPLS, which was alluded to in Part IV. The advantages and disadvantages of routing versus layer 3 switching, and the question of when to use a router and when to use a switch are detailed here. It explains how MPLS clearly distinguishes between path determination (which should mainly be performed at the edge) and packet forwarding. Packet forwarding is very fast because once the packet is labeled at the network edge, it quickly traverses the network, only requiring the label switching routers to perform the label processing without actually performing any lookups in the routing tables. Packet forwarding will be getting faster in the future with optical networking and the development of optical switches that can operate within MPLS networks, perhaps at the dense wave division multiplexing (DWDM) level with multiprotocol lambda (wavelength) switching.

The appendices include an acronym glossary, standardization notes, troubleshooting guidelines, port transmission speeds, and some general useful numbers including port numbers, hex to binary conversion and multicast addresses.


Rating:
Summary: Helpful for both beginner and professional
Review: Routing and Switching: Time of Convergence? is "All in One" book covering all aspects of modern networking.

Time of Convergence? is the proper book for people who want to learn what the internetworking is, which devices make internetworking infrastructure, how and why communication protocols exist and other issues of traditional networking. Furthermore progressive technologies and trends are discussed. This book is also well suitable for internetworking experts who would appreciate all important information collected in one place.

Both range and depth of information presented are carefully selected. Details and facts are sufficient to satisfy the internet professionals. On the other hand all elementary principles are adequately described and are clear for understanding.

Chapters are set up in logical and chronological structure reflecting the OSI reference model and the history. Reader is guided through architectures of communication systems, types of networks and technologies. Problems of switched and routed networks are discussed next. The book is not limited only to internet networks based on Internet Protocol (IP) but covers also non-IP networks like AppleTalk, IPX/SPX, DECnet etc. The last third of the text points to progressive topics like increasing of the communication speed, quality of services issues, MPLS and optical switching.

The concept of Snapshots and Hints for summarizing key facts and Quick Tips for underlining not so obvious ideas makes orientation and understanding easier. Standards and RFC Watches are used to summarize standards mentioned in previous paragraphs. The book is not filled up by standards citations but it is simple to reach them in this way.

Useful parts of the book are appendix sections. It contains abbreviations, standardization overview, quick guide to troubleshooting common networking issues, overview of transmission speeds, IP protocol and port numbers, multicast addresses, binary/decimal/hexadecimal number conversion table and links to recommended sources. It is not necessary to search RFCs or other sources. You will save your time simply opening the proper page.

Time of Convergence? is perfect, complex, clearly structured and easy to read internetworking handbook. You can read it word by word as well as only pick up topics you are interested in right now and improve or align your knowledge.

Rating:
Summary: Helpful for both beginner and professional
Review: Routing and Switching: Time of Convergence? is "All in One" book covering all aspects of modern networking.

Time of Convergence? is the proper book for people who want to learn what the internetworking is, which devices make internetworking infrastructure, how and why communication protocols exist and other issues of traditional networking. Furthermore progressive technologies and trends are discussed. This book is also well suitable for internetworking experts who would appreciate all important information collected in one place.

Both range and depth of information presented are carefully selected. Details and facts are sufficient to satisfy the internet professionals. On the other hand all elementary principles are adequately described and are clear for understanding.

Chapters are set up in logical and chronological structure reflecting the OSI reference model and the history. Reader is guided through architectures of communication systems, types of networks and technologies. Problems of switched and routed networks are discussed next. The book is not limited only to internet networks based on Internet Protocol (IP) but covers also non-IP networks like AppleTalk, IPX/SPX, DECnet etc. The last third of the text points to progressive topics like increasing of the communication speed, quality of services issues, MPLS and optical switching.

The concept of Snapshots and Hints for summarizing key facts and Quick Tips for underlining not so obvious ideas makes orientation and understanding easier. Standards and RFC Watches are used to summarize standards mentioned in previous paragraphs. The book is not filled up by standards citations but it is simple to reach them in this way.

Useful parts of the book are appendix sections. It contains abbreviations, standardization overview, quick guide to troubleshooting common networking issues, overview of transmission speeds, IP protocol and port numbers, multicast addresses, binary/decimal/hexadecimal number conversion table and links to recommended sources. It is not necessary to search RFCs or other sources. You will save your time simply opening the proper page.

Time of Convergence? is perfect, complex, clearly structured and easy to read internetworking handbook. You can read it word by word as well as only pick up topics you are interested in right now and improve or align your knowledge.

Rating:
Summary: What I wish people prepared with for advanced study
Review: The author walks a wonderful line between the confusing oversimplifications found in many networking overviews and beginning vendor courses, and books for experienced designers and protocol architects. As an author and consultant in design, someone who read and understood this book would be ready to go into the "next level" of knowledge. Again in walking the fine line, the descriptions of protocols makes sure the reader knows WHY the protocol does what it does, and then introduces HOW to a leven of detail that is appropriate but not overwhelming. There are excellent references conveniently in the body of the text, but the author avoids the trap of filling a book with large chunks of text from standards documents.