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As before, we will be focusing on how to pass the examination
by explaining exam content, types of questions to look out for and the vital knowledge
that you need to gain that all-important ‘Pass’ mark.
General Advice
This is the one MCSE examination that is not tied to a specific Microsoft product, but
instead is designed to test your overall knowledge of general networking theory,
components and terminology. However, there is, without doubt, a slant towards NT (and even
Windows 95) in the questions, so my advice to those who are not already familiar with
Windows NT is to revise for and pass your NT examinations first and then worry about
Networking Essentials.
Another unique thing about the Networking Essentials examination is that Microsoft does
not have an Official Curriculum trainer-led course available to learn it. Instead it
offers a self-study ‘kit’ which incorporates a book and a CD-ROM from which they
recommend you revise prior to sitting the exam. This self-study kit is published by
Microsoft Press and is available in all good PC bookshops. I strongly recommend buying it
(or one of the many self-study books from other publishers) even if you are already
proficient in networking. The self-study kit is invaluable because it shows you how
Microsoft uses terminology, how Microsoft defines differences between components and how
Microsoft wants you to answer the questions in the exam.
Exam Breakdown
The Server exam has 4 sections: Standards and Terminology, Planning, (we will examine
these two sections this month) Implementation, and Troubleshooting (which we will look at
next month). As usual, we will take each section separately, list the different subjects
that you could get asked about in that section and then give hints and tips on the types
of pitfalls and traps you might come across in any one particular question.
The Standards and Terminology Section
What to Revise
Client/Server Vs Peer-to-Peer Network Models, Network Connectivity Devices, Cabling
Components, Media Access Models, Share-Level Vs User-Level Security Models, Routing
Tables, Layers of the OSI Model, WAN Topologies, LAN Topologies, Protocols, NDIS and ODI,
The Universal Naming Convention, Connection-Oriented Vs Connectionless, Dial-Up Protocols,
Project 802 Standards, Baseband and Broadband Signalling, Wireless Connections.
Watch For:
1. Network Connectivity Devices - Make sure you know
definitions for each of the following, when to and when not to employ them and at which
layer/s of the OSI model they work: Repeaters, Bridges, Routers, Brouters and Gateways.
2. Cabling Components - You will get a lot of questions on
this subject so thoroughly revise the following: Cabling Topologies, Cable Types, Media
Access Methods, Connectors, most common combinations (e.g. Star Wired Token Ring using STP
cabling with IBM connectors) and when you are likely to see them being used. Make sure you
know all the facts and figures for each component or topology (e.g. 10BaseT segments have
a maximum length of 100 metres).
3. Routing Tables - Make sure that you are confident that you
understand what a routing table is, what its purpose is and which protocols and
connectivity devices make use of them. Watch out for ATP (part of the AppleTalk protocol
suite) as you may get asked a question about it and whether or not it can use a routing
table (it can).
4. Layers of the OSI Model - The OSI model is the most
important subject, after cabling, to get right. You will need to understand
Microsoft’s definitions for the responsibilities of each of the seven layers,
including both of the sub-layers of the Data Link layer. You must also be aware of which
layer each hardware and software networking component operates at.
5. WAN Topologies and Components - You will be asked to
define the different WAN standards – ISDN, X25, Frame Relay, ATM, etc, the different
topologies – point-to-point, Permanent virtual circuits, etc, and capacities –
ISDN Primary and Basic rate, T1, T3, etc.
6. Protocols - You must be able to define each of the
following protocols, their common usage, advantages, disadvantages, where they fit in the
OSI model (and in the case of TCP/IP, each protocol within the suite): TCP/IP, NetBEUI,
NWLink, AppleTalk, DLC. You may well be asked how to add a protocol to the NT environment.
7. NDIS and ODI - Be prepared to answer questions regarding
the differences and similarities between NDIS and ODI, how many network cards and how many
protocols can be bound together using NDIS and ODI, the different NDIS versions and the
difference between real mode and virtualised components.
8. Connection-Oriented Vs Connectionless -
Connection-oriented protocols guarantee the safe and error-free delivery of a message over
the network, but in doing so incur severe penalties in terms of speed and efficiency.
Connectionless protocols are the exact opposite of this – they do not guarantee safe,
error-free delivery but operate much faster and more efficiently. User data (such as a
spreadsheet document or a report) is almost always sent via a connection-oriented
mechanism in order to ensure that the date is not lost. Much of the ongoing background
traffic generated to support the network (such as browser announcements) is sent via a
connectionless mechanism in order to maximise network efficiency.
9. Dial-Up Protocols - Two dial-up protocols are supported by
NT – PPP and SLIP. Of the two, SLIP (Serial Line Internet Protocol) is the older and
less versatile. SLIP only supports TCP/IP and requires either manual configuration of IP
addressing information or else a custom script as it does not support dynamic IP address
allocation. PPP (Point to Point Protocol) supports TCP/IP, NetBEUI and NWLink and also
supports dynamic allocation of IP addressing information. NT supports PPP in both client
and server formats, whereas SLIP is supported only for the client side.
10. Project 802 Standards - Project 802 was developed to
further define and refine standards for the Physical and Datalink layers of the OSI model.
Make sure you know what each 802 standard defines.
11. Baseband Vs Broadband - Baseband describes using the
entire frequency spectrum of the medium to send a signal. This is usually associated with
digital signalling. Broadband describes using different frequencies to simultaneously
transmit multiple signals and is usually associated with analogue signalling.
The Planning Section
What to Revise:
Use of Connectivity Devices
Selecting Appropriate Cabling
Bus Types
Differences between Bridges and Routers
Sliding Windows
Selecting the Appropriate Connector
Selecting the Appropriate Network Protocol
Selecting the Appropriate Network Access Method
Selecting User-Level or Share-Level Security
Multiplexing
RAID
Selecting the Appropriate Wiring Topology
Using Subnet Masks
Avoiding Crosstalk
Repeating a Broadband Signal
Routing Protocols
The Purpose of a Transceiver
The Purpose of SNMP
Watch For:
1. Use of Connectivity Devices
You will need to answer scenario-based questions on choosing the appropriate connectivity
device to use in the given circumstances of the question. You will also be asked for
definitions of the tasks of each connectivity device and the layer/s of the OSI model it
operates in.
2. Selecting Appropriate Cabling
You will need to answer scenario-based questions on choosing the appropriate cable type,
based upon the information provided in the question. To answer this, make sure you know
your maximum and minimum cable lengths, the correct cable type or types to use for a given
topology (e.g. star wired) and the correct types of connector.
3. Bus Types
You get asked which bus type is the best to use for a network interface card. The answer
is an EISA bus with shared memory.
4. Differences between Bridges and Routers
The differences between bridges and routers are not immediately obvious, as they both
perform very similar tasks. Both bridges and routers subdivide a network into subnets and
can connect dissimilar topologies and cable types using a routing table to make forwarding
decisions, but differ in the way that they do so. A bridge works at the Data Link layer of
the OSI model and uses the physical (MAC) address of each node to build its routing table.
A router works at the Network layer of the OSI model and uses logical addresses (such as
the IP address for TCP/IP) for each subnet to build its routing table. Bridges are able to
route any network protocol, whereas routers can only route protocols that use a logical
addressing scheme. Bridges can only forward messages to a node in one direction, whereas
routers can forward messages to a host in multiple directions. Bridges propagate
broadcasts to all subnets, whereas routers do not (by default) propagate broadcasts.
5. Sliding Windows
Used by network protocols such as TCP/IP, each node has a send window and a receive
window. The size of the send window determines the amount of data that can be sent across
the network in one go, before waiting for an acknowledgement from the receiving computer.
The size of the receive window determines the amount of data that can be received in one
go before sending an acknowledgement to the sending computer. The acknowledgement acts as
a basic guarantee that the data has arrived safely and enables the sending machine to
slide forwards to the next set of data to be sent. To optimise the sliding windows
environment, it is recommended to have the send window set to a larger size than the
receive window.
6. Multiplexing
You will need to understand the use of multiplexing. Multiplexing is the combining of
multiple data messages onto a single transmission signal, which is then sent across the
media and divided back into its constituent messages at the other end. This system makes
for far more efficient usage of transmission media and is commonly used in WAN connections
and telecommunications. The devise used at each end of the transmission is called a
multiplexor.
7. RAID
Make sure you know definitions for each RAID level and, what mirror sets and stripe sets
with parity are used for.
8. Repeating a Broadband Signal
The device used to repeat the signal in a baseband transmission is called a repeater, but
the device used to repeat the signal in a broadband (analogue) transmission is called an
amplifier.
9. Routing Protocols
Learn the differences between OSPF and RIP. RIP is the only routing protocol that can be
installed as a service on Windows NT computers acting as routers and uses a
distance-vector algorithm.
10. The Purpose of a Transceiver
A transceiver converts the internal, parallel signal of the computer into a serial signal
suitable for transmission over a network and vice versa. Most network interface cards have
built-in transceivers, but the 10Base5 (thicknet) topology uses external transceivers.
Richard Adams is an Executive Technical Director for
Additional Resources, an IT training company.
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