In previous months, we looked at all of the domains on the new version of the popular CompTIA Network+ certification exam (N10-006) except for the final one: Industry Standards, Practices, and Network Theory. This month we will look at that last domain, weighted at 16 percent of the total exam, and the topics that comprise it.
There are 10 subdomains under the standards and practices (and theory) label and they bounce around in terms of subject matter. To illustrate this, the table below lists them in the order in which they appear in the CompTIA exam objectives:
As with all the domains and topics on this exam, a combination of common sense and a little bit of knowledge and experience (9 to 12 months of work experience in IT networking) is the best tool for helping you pick the right answer on multiple-choice exam questions.
What You Need to Know
The following discussion is intended to represent a study guide for this domain. It does not include every topic (space will not allow for that), but it covers most of the main topics. Most of the bullets and tables are very straightforward but if you don’t understand any of the subjects, then you would be well-advised to research them further.
- As data is passed up or down through the OSI model structure, headers are added (going down) or removed (going up) at each layer: a process called encapsulation (when added) or decapsulation (when removed).
Table 1: Summary of the OSI Model
- Connection-oriented protocols such as TCP (Transmission Control Protocol) can accommodate lost or dropped packets by asking the sending device to retransmit them. They can do this because they wait for all the packets in a message to be received before considering the transmission complete.
- On the sending end, connection-oriented protocols also assume that a lack of acknowledgment is sufficient reason to retransmit.
Table 2: Port Assignments for Commonly Used Protocols
- In addition to providing best-effort delivery, IP also performs fragmentation and reassembly tasks for network transmissions.
- Fragmentation is necessary because the maximum transmission unit (MTU) size is limited in IP. In other words, network transmissions that are too big to traverse the network in a single packet must be broken into smaller chunks and reassembled at the other end.
Table 3: TCP/IP Suite Selected Summary
- Type C fire extinguishers are used for electrical fires.
- The major drawback to gas-based fire suppression systems is that they require sealed environments to operate.
- Main distribution frame (MDF) and intermediate distribution frame (IDF) define types of wiring closets. The main wiring closet for a network typically holds the majority of the network gear, including routers, switches, wiring, servers, and more.
- Cable trays can be used to carry cabling throughout the building. Trays run overhead and usually either resemble racks/wire shelving (having open bottoms) or have solid bottoms to blend in easier with the aesthetics of the environment. Trays are often used when reconfiguration may be a regular thing or it is too costly to run wiring through pipe, walls, and other building fixtures.
Table 4: Standard Business Documents
- Network documentation does not happen by accident; rather, it requires careful planning.
- When creating network documentation, you must keep in mind the audience you are creating the documentation for.
- Documentation is used to take technical information and present it in a manner that someone new (yet qualified) to the network can understand.