13 Skills Every IT Pro Should Have
Author: Linda Leung
Abstract
No matter which IT field you're working in, there are several
skills that are useful for every IT professional to know. In this
white paper, seven experienced IT professionals working in the
networking, programming, project management, and security fields
share what they believe are the most important skills that every IT
pro should know.
1. Programming
Even if your job doesn't require software development, it's
useful to understand how applications are built because everything
we do - from following Twitter feeds to filling out expense forms -
is enabled by software. IT professionals with an academic
background in computer science will likely have done some
programming as part of their education. For others, there are many
ways of learning programming.
Martin Harvey, PMP, managing consultant at Coroware, says: "The
language I'd recommend learning would be any C-based language. It's
a fairly common language that can be found in Microsoft and Java
platforms, but it's not trivial. At the other end of the spectrum
there are more interpretive languages such as Visual Basic and
Python. It's easy to mess around with Visual Basic and Excel macros
on your PC. You'll learn about the fundamentals of programming and
the logic of how data is stored."
2. Learning from the book The Mythical Man-Month
Publisher Addison-Wesley Professional describes the book The
Mythical Man-Month as "influential and timeless." Originally
published in 1975, author Fred Brooks shares his experiences as
project manager for IBM System/360 computer family and then for
OS/360, its massive software system. Brooks made several mistakes
including adding more workers to a project falling behind schedule,
and underestimating the time it would take to complete a project.
The book was republished in 1995 with new thoughts and advice from
Brooks. Harvey says: "It's like 100 things your mother told you. I
still made some of the mistakes after reading it. But if you read
the book, maybe you won't make the mistakes or you will recognize
that you are making them and know when to duck."
3. Understanding the basics of networking
"The network is how everything connects and every IT pro should
know how that happens," says George Morton, a dual CCIE (Cisco
Certified Internetwork Expert). Morton says IT pros should study
and understand the following:
Who is Cisco, Juniper, etc., and what do they offer. "Knowing
that Dell makes switches won't get you to the top of the game,"
says Morton.
- TCP/IP and IP addressing
- Network Address Translation and Port Address Translation
- IPv6. "It is coming, and the sooner you get on board the better
for your career," Morton says.
- IP telephony: packet vs. switched
- What are routers, switches, and firewalls?
Basic Access-List configuration for Cisco
To be able to read a Cisco IOS running configuration; not so you
administer the router but just understand what it is or isn't doing
for you.
Be familiar with guidance from the National Security Agency's
Information Assurance for securing your network.
Morton recommends several books:
Cisco Networking Simplified
A first-class introduction to networking
Cisco IOS Cookbook, Second
Edition
This book should be on every IT manager's desk. I use it to build
some of the world's most complex networks. Why? It's easy to read,
creates standards for the client, and covers almost everything I
need.
JUNOS Cookbook and ScreenOS
Cookbook
4. Know security best practices within your IT
discipline
Given that businesses are moving or have moved aggressively
toward relying on online digital resources to conduct their
day-to-day operations, it is critical that those resources stay
highly available and secure. Jamey Heary, CCIE, a security
consulting systems engineer at Cisco, explains: "Without exception,
the IT discipline that you choose will have security risks
associated with it. To be successful at your discipline you must be
aware of what those risks are and what the best practices are to
lower those risks. You must understand the risk/benefit trade-offs
as well so you can make the right business decisions and apply the
proper amount of security controls. Too much security is just as
bad as too little. With too much security it is likely that your
users will view your IT services as unusable. With too little
security you open yourself up to attack and risk great damage to
the company, customers, and the brand name you work for. Security
is a balancing act that you need to understand (at least at a high
level) for your specific job role.
"For network security you can implement security controls like
firewalls, virtual private networks (VPNs), intrusion
detection/prevention systems (IDS/IPS), etc. For Windows Server
security, you can implement controls like strong passwords,
expiring passwords, disk encryption, antivirus, etc. For e-mail
security, you can implement antispam, antivirus, antimalware
engines that scrub the mail before delivery. Every IT discipline
will have its own set of security best practices that should be
adopted to decrease your risk of being compromised by a
hacker."
5. The benefits and caveats of capital
expenditures
IT is a capital-intensive business, and all IT people should
understand the process of capital investments, says Michael Morris,
CCIE, CCDE (Cisco Certified Design Expert), a communications
engineering manager at a $3 billion high-tech company.
He says: “IT makes huge capital investments. Capital investments
are purchases (servers, network gear, software applications) that
are bought with cash, but are categorized as assets. The actual
“cost” of these purchases is not incurred immediately. Instead,
this cost is expensed in the form of depreciation, generally over
three years.
This provides the IT organization the ability to buy equipment
now, but doesn’t cause a huge impact to the company’s bottom line.
This is good, because companies can get what they need
immediately.
“The problem is that these costs (depreciation) are now “fixed
costs” and cannot be avoided. Every quarter, a portion of the cost
of that new server you bought a year ago will hit the books (both
the IT budget and the company’s expenses). If the economy gets
worse (sound familiar?), these costs cannot be avoided so companies
must find other costs to cut. These other costs - called “variable”
costs - include employees, who are often the first to go.
“Capital spending is a balancing act. It is needed and provides
a great way to spread out costs, but can lead to sticky situations
when hard choices have to be made.”
6. IP addressing
At the root of almost all online communications today is the
Internet Protocol (IP). At the heart of IP communications is IP
addressing. Jamey Heary explains: “Knowing how IP addressing works
is crucial knowledge for any IT professional. Every host, server,
router, firewall, and network device must have at least one IP
address assigned to it in order to communicate with other network
hosts/devices. If you assign IP addresses incorrectly not only will
the device not be able to “talk” on the network, but you could also
do harm to existing network devices.
“An IP address is a numerical 32-bit numbering scheme used by
the IP protocol for identifying where something is. In many ways,
an IP address is analogous to your house address. For example, to
send a letter to someone I first put my return address on the
envelope and second I put their house address on the envelope. The
source IP address field in an IP packet is just like the return
address on an envelope. It defines who sent or is sending the data
packet. The destination IP address field in an IP packet is just
like the house address on an envelope. It defines to whom I want
the data packet to go.
“An IP address is represented in dotted decimal notation; four
numbers from 0-255 that are separated by a decimal point
(172.16.1.200). The IP address itself is broken up into two parts,
the network address and the host address. The network address is
very much like a zip code on an envelope; it provides the general
area to deliver the message to. The host address portion of an IP
address is very much like the house number and street address on an
envelope, it defines exactly what location to deliver the message
to.
The post office will quickly sort mail based on zip code, and
send it to a local zip code post office where the street number,
etc., are then parsed and given to the correct postman for delivery
to the right house. In IP, the post office job is done by IP
routing. It looks at the network portion (also called a subnet) of
the IP address and delivers the data packet to the general location
or subnet.
Once at the subnet, a switch takes over (acting as the postman)
and delivers the data packet to the host using the host portion of
the IP address. Host IP addresses must be unique for every device
in a given subnetwork. For the same reasons you can’t have two “12
East Lane Rd, Tinytown, NY 22121,” addresses, you also can’t have
duplicate IP addresses. If you did, there would be no way to
uniquely identify who to deliver a message to. Note:
There is a thing called Network Address Translation in IP that
helps with this problem, but that is for another discussion.
7. Perl and Tcl
Jimmy Ray Purser, network engineer at Cisco
and technical co-host for Cisco’s TechWise and BizWise TV, believes
all IT pros should understand and be able to write a simple Perl or
Tcl script. “The entire world of networking opens up to an IT pro
who can write even the most basic of scripts.” It is easier to
learn than IP subnetting, and there are many great free resources
on the Internet to learn it,” he says. He points to two useful
resources: Perl scripting 101 and Tcl scripting 101.
8. Using the OSI model for network
troubleshooting
Networks are built on the OSI (Open Systems Interconnection)
reference model, a seven-layer stack where control is passed from
one layer to the next. Having an understanding of the model will
enable you to better troubleshoot networking problems, as Michael
Patterson, co-founder of network monitoring company Plixer
International explains. Below, Patterson maps the seven layers to
their related troubleshooting questions.
Physical layer: Do you
understand the topology? Is the user plugged into the
network?
Data Link layer: Can the technician use a packet
analyzer like Wireshark?
Network layer: Does the tech understand IP logic
and subnet masks? How is a packet routed on the businesses
network?
Transport layer: How does TCP (Transmission
Control Protocol) operate vs. UDP (User Datagram Protocol)?
Is it an ARP (Address Resolution Protocol) packet or an IP
Frame?
Session layer: Can the user connect to or ping the
server? What is the time out for idle connections?
Presentation layer: Does the tech understand basic
HTML code, SNMP, and ASN.1?
Application layer: The tech may not understand the
application, but he or she should understand how applications can
impact the network.
The technician should also be able to set
up NetFlow on Cisco equipment or the industry standard sFlow to
capture traffic data for analytical purposes.
9. Packet
sniffing
Before you even use a packet sniffer - a
network monitoring tool for network troubleshooting - understand
how to set it up. “This means understanding the impact of the NIC
(network interface controller) on accuracy and performance; when to
use a SPAN (Switched Port Analyzer) port over a TAP (test access
point) and vice-versa;
and when to TCPDump/Tethereal over Wireshark,” says Jimmy Ray
Purser. You’ll need to understand the various start-up options and
how to configure Berkeley Packet Filters to clean up your packet
stream, he adds.
10. Google is your
friend
IT infrastructure expert Rocco (he didn’t
want his full name revealed) says: “Don’t be afraid to ask for
help.”
Oftentimes, Google is your best friend. Rocco says: “I have a real
tough time remembering acronyms. A quick link to a current list is
always helpful (Google it!). For example, I’ve been working on Web
infrastructure a long time; I know all the components. A business
development guy asked me to set up a LAMP server for testing. This
is how I remember the definition of LAMP:
“L - Linux. I don’t set up
Windows servers anymore so of course it will be Linux
A- Apache. Come on get real. Is there really an
alternative to Apache?
M - MySQL. Well duh! I’m not paying for Oracle
unless I really need to.
P - PHP. It’s been a long, long time since I setup
Apache without PHP.”
Rocco adds: “He could have asked me to set
up a Web server and database and receive an instant answer,
but instead he threw out acronyms he probably didn’t
understand.”
11. Create a good PowerPoint
presentation
All IT professionals - from VPs to
individual engineers - need to be able to construct a logical and
visually appealing PowerPoint presentation to communicate to other
people, suggests Michael Morris. And don’t think you can get away
with black-and-white PPTs with page after page of bullets. “Use of
a slide master template along with proper logos and colors are a
minimum,” Morris says. “Proper use of charts, models, and diagrams
will also enhance your message and engage the audience.” And
remember, when presenting to anyone more than two positions above
you (like the CIO), you need to condense your presentation down to
three slides. “If you can’t get it into three slides, it’s too
confusing and too much for an executive. Consider yourself a PPT
expert when you can create a visually engaging presentation with
proper corporate logos and colors using a variety of tables,
charts, and models in only three slides.”
12. Keep your e-mail under
control
It’s easy to be overwhelmed by your e-mail
inbox, but being 2,000 e-mails behind is just not acceptable these
days, says Michael Morris. “For most companies, e-mail is the
primary communications medium between people and especially groups.
Being 2,000 e-mails behind and complaining you can’t catch up is a
poor excuse. Today there are filters, organizers, alerts, webmail,
and this new thingy call BlackBerry. Stay on top of your e-mail. No
excuses.”
13. Know why network delay is
bad
Almost all traffic that runs across
networks today - including the Internet - uses Transmission Control
Protocol (TCP). TCP requires an acknowledgement (ACK) from time to
time during a data transfer session. When TCP reaches a point where
it determines an ACK is needed, it stops sending traffic and waits
for an ACK from the other end of the TCP session. Only after an ACK
is received does the data transfer start again.
Michael Morris explains: “In this setup,
when the user and the server are right next to each other (let’s
say in the same building), the ACK arrives in very, very short time
(under 1 ms). This creates a very short pause in the data transfer
session. The TCP algorithm can then ramp up the data transfer rate
to near 1Gbps.
“However, when the distance between user
and server is great, it can take a while for an ACK to reach the
server. It could take 300 ms to go from the U.S. to India over a
WAN (300 times longer than when user and server are in the same
building). Thus, the data transfer pause is much longer. TCP’s
algorithms then can only send traffic at a much slower rate, which
impacts user performance.
“All IT people should understand this
simple paradigm. As network delay increases, data transfer rate
will fall, precipitously. Remember this when your users in Germany
are saying the server in California is slow in the
morning.”
This is by no means an exhaustive list of
all the skills that IT pros need to know. We would like your
thoughts on what other skills you feel are essential today. Please
send your thoughts to linda.leung@globalknowledge,
and we’ll incorporate your feedback into future lists.