The document provides a high-level overview of networking concepts for public libraries, including wired and wireless networking. It discusses Ethernet local area networks using twisted pair cabling of different categories (Cat 5, Cat 5e, etc.) to connect computers to a switch. It also covers wireless networking standards like 802.11b, 802.11g, and how wireless networks connect via access points to the wired network infrastructure. The document aims to explain core networking concepts in simple terms while acknowledging more details are omitted.

1. Are You Experienced?
Exploring User Experience
in Public Libraries
Networking: Wired and Wireless
(a grossly oversimplified tour)

2. A few simple concepts…
Library networking can be broken down into
a few simple concepts*
*especially if I leave out some important details
Many types of networks exist, but if you are
asked to guess, guess that a library is using
an Ethernet LAN (local area network) over
twisted-pair cabling.

3. What is an Ethernet network?
Ethernet is the most common LAN
technology, and it is specified in the IEEE
802.3 standard. Coaxial cable (like what you
see for cable TV) was used originally but has
since been replaced by twisted pair cable and
sometimes fiber optic.

4. Cables differ in the amount of bandwidth
they can support and distance for which
they support it.
If you want some quick details, see the PC
magazine encyclopedia:
www.pcmag.com/encyclopedia/term/42781/ethernet

5. Common categories of twisted pair cable in
a typical library LAN include:
Cat 5 100Mbps
Cat 5E 1000Mbps
Cat 6 1000Mbps, etc.
…up to fiber optic, which is real fast, up to 10
Gbps (and expensive, and delicate, so it is used
only in certain situations).
Mbps = Megabits per second
Gbps = Gigabits per second
1000 megabits = 1 gigabit

6. You can identify the type of UTP (unshielded
twisted pair) cable by looking at it because
its category is marked on it at intervals.
Feel free to crawl around to look at cables…

7. So how are computers
connected to each other?
Ethernet can also include wireless…but at its
core a network is going to start out wired.
It is possible to build a sort of network
architecture where two or more “equal”
computers can connect to each other and
share files, etc. without any central
administration (peer-to-peer) -- but that is not
what your library uses…

8. So what do we use?
If you must guess, say: "What is a client/server model?

9. What do you need for a
client/server model?
At least two computers that are somehow
connected. One is a client, one is a server.
In this sample, the client computer (where the library
staff member sits) is connected to a server (where
the ILS software lives) by twisted pair cable. The two
computers can communicate (the server serves the
client, of course).

10. In reality, these computers are really all wired to a switch --
not directly to each other – because a network will have
more than two computers. They communicate through the
switch as if they were directly connected.
The type of switch and category (“cat”) of cable makes a
difference, of course, in how fast data can be transmitted
(remember, usually given in Mbps – Megabits per second).

11. So here is your simple Ethernet network, with computers
communicating via a switch and UTP cable…and it can
grow to an enormous size. Just connect more devices.
Your ILS serverYou
FYI: The “connectors” for UTP cable is
the RJ45 jack, which resembles the
traditional telephone jack – but it is not!

12. Connect network-ready printers, copiers, security cameras,
more computers, etc.
Does your network stop growing when you fill up the ports
on the switch?

13. You can add more switches to your network, and more
devices!
Hey, I made one big virtual switch.

14. Are you limited?
Just by your imagination!
Oh, and the laws of networking, which are
way too much to explain here, but you get
the idea. For example, I did not explain IP
addresses and how your computer gets
one…but that is the empire of your network
technician.

15. So what can a non-network
expert do to a network?
You can extend it by adding inexpensive
switches so that one data jack can serve
more than one device.
This cable goes to the one
data jack nearby in the
wall…and two or more other
computers can join the
network!

16. …and thus you are not bound by the number of data jacks
you have in your walls.

17. So what else can a non-network
expert do to a network?
You can make sure your cable is up-to-date
by checking on the most recent standards..
Hint: If you are using Category 5 or below,
you are behind. A network can only transmit
data as fast as its slowest element (cable,
switch, etc.).

18. “True Confessions” time
Not that long ago I was helping a nearby
small public library add some devices to its
network…but things were not going well.
I could just not get some things to work!
I will spare you the boring details…but…

19. I knew this library hired someone to run
some cable a few years earlier, and most of
it was hidden in the attic.
Up I went to discover – to my dismay – that
long runs of the cable up there were … gasp
… Cat 3 cable!
Cat 3, popular in the early 1990s, delivers
up to 10Mbps (aka: slow as molasses)

20. I know that number means nothing to many
of you…but it is not good. Cat5e was the
current standard at that time, and Cat5e
delivers up to 1000Mbps.
So that library was essentially cheated by
not understanding basic cabling.
This is the only nice-looking copy-right
free image I found when I Googled Cat3
cable. I will assume it is an angry cat
destroying Cat3 cable.

21. But how does a network get on
the Internet?
Any network message
you need to send to a
non-local address
goes to a router.
The router forwards it
to another router (and
more) until it gets to
the final destination.

22. So the router connects a LAN to
the Internet?
your router
Internet
Yes. And you
become part of
a larger
network.

23. How do I get on the cloud?
If you are on the Internet, you are on the
cloud. Many ILS vendors now offer cloud-
based services -- hosted services -- so that
you don't need to run your own server(s).
And it is a growing trend.
Now get ready for a long quote:

24. "The transition to cloud computing provides a significant
increment of industrywide growth. A software-as-a-service
(SaaS) economy model trades higher upfront costs,
incurred by libraries for equipment and software licenses,
for a comprehensive annual subscription fee…. Even for
server-based integrated library systems, libraries
increasingly opt for hosted options as they acquire new
products, instead of replacing outdated equipment
underlying existing installations.“
--Marshal Breeding. Library Systems Report 2014:
Competition and strategic cooperation. American Libraries.
americanlibrariesmagazine.org/2014/04/15/library-systems-
report-2014/

25. Internet
hosted ILS
on the cloud
Don't need that local
ILS box any more!X

26. Is networking that simple?
No it is not that simple. We have not even
discussed firewalls, IP addresses, and other
stuff, but maybe you have enough to give
you a general idea.
What else could you want to know if you are
not a networking expert?

27. How do I get a
wireless network?
It all starts with your wired network.
A wireless network uses Access Points that
are cabled to the wired network. The Access
Points (APs) transmit the network signal to
wireless devices.

28. Is it that easy?
Access
Point

29. No, of course not…
But that diagram shows you the major
concepts. Wireless technology follows the
IEEE 802.11 standard (yes, another
standard for you to know).
For wireless you must consider that more
recent access points can transmit
faster…and more recent devices (laptops,
etc.) have faster wireless network cards.

30. 802.11 wireless standards?
There are several flavors, the most common being:
802.11b -- supports bandwidth up to 11 Mbps
802.11g -- supports bandwidth up to 54 Mbps
802.11n -- supports bandwidth up to 300+ Mbps
802.11ac -- supports bandwidth up to 1300+ Mbps
Gee, sounds fast…and it is getting faster…

31. Usually fast enough…
In reality, you will never get the top speeds. Speed
also depends on distance (the farther away the
device is from the AP, the lower the speed)
number of users, and other factors…
See: Wireless Standards Explained:
compnetworking.about.com/cs/wireless80211/a/aa80211standard.htm
And don't forget that your wireless device adheres
to one of the 802.11 standards! Does it matter?

32. Can we mix and match
wireless standards?
Because we have so many old and new devices
along with old and new wireless APs, they do (for
the most part) work with each other. Backwards
compatibility is built in.
802.11ac can communicate with the older
standards -- which is good, because many libraries
that went wireless a few years ago use 802.11b/g

33. So what can I do with scant
wireless network knowledge?
You know that your wired network can be
extended wirelessly. And if you are not
taking advantage or wireless networking you
are unfortunately not serving your patrons --
or yourself -- very well.

34. Does a wireless network make
my library vulnerable?
Unless you use some level of wireless
security (many options are available),
anyone can get on – just as if you left a staff
computer unattended.
And data transmission, being in the open, is
much easier for nefarious ne'er–do–wells to
intercept.

35. Realize also that unless your library is in a
windowless concrete bunker, your network
now extends outside your walls!

36. Is a wireless network worth it?
If you want to meet your users’ expectations
and serve users where they want to be
served (on the devices they want to use),
wireless is worth it.
FYI: WiFi traffic may overtake wired traffic
by 2018. So you really have no choice but to
give wireless access your attention.
(www.cisco.com/c/en/us/solutions/collateral/service-provider/ip-ngn-ip-next-
generation-network/white_paper_c11-481360.html )

37. What is my real network speed?
If you want to know the speed of your device
on a wired or wireless network, go to:
www.speedtest.net/
Remember that network speed
is commonly given in Mbps
(Megabits per second). If you
can't provide a download speed
of at least 1.5Mbps you will not
meet PL standards in Indiana.

38. Am I more dangerous now that I
have a little bit of knowledge?
Perhaps. But if you can start to understand
your network, you gain the power of a
superhero.