Guidance for a measurement titled

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Guidance for
a measurement titled


“Measurements for local computer networks”




VOL 1








Written by
:

Telecommunication pattern laboratory of Department of
Telecommunication and Telematics in September 1995


First edition
:

Department of T
elecommunication and Telematics

Telecommunication pattern laboratory

September
1995


Composed by
:

György

Horváth
,
engineer

Tel.:

18
-
65

MAIL:

horvaath@bme
-
tel.ttt.bme.hu


i


Content









Usage of guidance


Concept of LAN, and the OSI ref
erence model


Building elements of the network of Department


Cabling


Testing of cables


Testing of line signals


IEEE802 series of recommendation


SIEMENS K1
102 type of LAN protocol tester


Databases of K1102


Mandatory literature


Recommended literature


Appendix 1. Ethernet Vendor codes



Appendix 2. Codes of the Etherneet Type field






1


About the usage of the guidance


This guidance was prepared for a measurement of Telecommunication and
Communication Networks of

“A” module laboratories of

Electrical Engineering
Department
titled “Measurements for local computer networks”. Its primer t
ask is to
introduce students through some examples to the basic methods of testing the local
networks.

On the one hand it presents the network of Department, following the layers of OSI
reference model, and then presents the services of a protocol tester,

and the method
of its usage.
.

We assume, that the reader has some basic user knowledge of
IBM
-
PC
typed
personal computers, and
Novell and
Unix (TCP/IP)
network applications.

This material is a guidance for topics mentioned below:



Co湣ept of
LAN,

a湤 t桥
OSI refere湣

model



B畩ldi湧neleme湴s of 湥twork of t桥 Departme湴



P桹hical la祥r
-

Cabli湧
-

Testi湧nof cables



P桹hi
cal la祥r


Testing of line signals



Series of r
散e
mme湤ation

IEEE802, LLC/MAC
, t桥


la祥r



SIEMENS K1102
t祰ed protocol tester



Traffic 来湥ratio測 mo湩t
ori湧n



Preparatio渠of tre湤s, statistics



Testi湧nof l
a祥r III.
p
roto
c

s, ro畴ers



Appli
catio湳, a湤 a correspo湤e湴
Gateway


T桩s doc畭e湴 (pl畳 a meas畲e
me湴 record) ca渠be fo畮u prese湴l礠at
N dri癥 of
PUB
field of ser癥rs of t桥 Departme湴 i渠s畢director礠of
MERESEK
\

\
DOC alkö湹癴árába渠 (
i渠 t桥 case of
GUEST, 癡杹g
MERES5,6

topic 湵nbers it is o渠 t桥
L dri癥)

at t桥 湡me of

LANVIZS.DOC (


MERES10.DOC).




Concept of
LAN
and the
OSI referenc
e m
odel


Concept of
LAN

(Local Area Network)
is the following according to the

IEEE
(Institute of Electrical and Electronics Engineering):


A ki nd of dat acommuni cat i on syst em, whi ch can make possi bl e
for numerous i nde
pendent t ool s t o communi cat e wi t h each ot her
di rect l y wi t hi n a medi um
-
si zed geographi cal fi el d, wi t h t he hel p
of a physi cal communi cat i on channel i nst al l ed for t hi s purpose,
wi t h a medi um capaci t y.


The present computer network of our Department is a typi
cal LAN, if the files,
printeable materials, electronic letters arosen during the computer work must be
forwarded with speed of 10...16 Mbit/sec among the approximately 100 pieces of
computers existing in building Stoczek working independently from each ot
her,
through thin Ethernet, token
-
ring, and thick Ethernet cables, that can be found in this
building miscellaneously (see next chapter).


OSI

(Open System Interconnection)
reference model connects systems, which are
open for a communication with other sy
stems. The model based on a recommendation
worked out by
ISO (International Standards Organisation)
is a hierarchic one, and
consists of seven layers built onto each other. They are the following:


7.

Applicat ion l
ayer



It provides direct services for t h
e users. In t he case of
LANs it is realized by
ne twork appl i cati ons

installed to
the workstation, or to the server, which have either a user
surface, or are able to complement the resources of the
given operation system with network resources, e.g.
file
tr
ansfer,
electronic correspondence, remote terminal
service, printing, etc.


6.

Presentation
layer



It provides semantically correct information for the
application to ensure the
pl atform
-
i nde pe nde nt

operation.

E.g. two different operation systems at th
e to
ends of the link, code conversion.
A typical problem is the

lack of this layer in case of transmission of the file over
the
TCP/IP proto
c
ol

(FTP), where the user must inform
the other side about the type of the transmittable file.



5.

Session

layer



It organizes the cooperation between the graphic entities,
s ynchroni ze s

their dialogues, and
transacts their data
changes.


3

4.

Transport

layer



It provides t he
e nd
-
to
-
e nd

delivery of messages through
the network. This layer can transmit messages
tra
nsparently with suitable packaging of the data flow.
E.g. it provides forwarding of the packages to the upper
layers in an
appropriate orde r
.

3.

Network

layer



It provides a network connection
, maintenance and
dissociation

between stations
containing c
ommunicating
entities besides an appropriate
route e xtracti on

(searching or designation).
E.g. connecting
-
transmitting
tools of LAN
(router)

must give this layer the most
powerful support, using the database describing the
topology of the network dynamical
ly and/or statically.

2.

Data link

layer



Tools, with that one, or more data connecting connection
can be generated, maintained, or dissolved. Task of this
layer is to expose, or improve errors occurring in the
physical layer during transmission. Accor
ding to the
recommendations of
IEEE 802.x
series, this layer broke
into two parts: one is the
LLC

(Logical Link Control)
which makes a logical connection control, independently
from the medium connection method; and the other is the
MAC

(Media Access Contr
ol)
, which controls the
availability of the given physical layer. E.g.

CSMA/CD,
t
oken,
connected, etc.

1.

Physical

layer



These are the tools and processes, which are necessary
for transmitting data, for generation, maintenance and
dissolving of physica
l connection between data connection
entities. E.g. this layer shows, that a bit series with no
sense for the layer can be taken away with what kind of
l i ne codi ng
, with what kind of
e l e ctri cal characte ri s ti cs

with what type of cable, and how far away.


Operation mode of the layers mentioned above can be conditioned with processes and

methods controlled well, which are suitable for a so called layer protocol.


In a computer connected to a network, unique layers of a reference model can have a
concrete sh
ape. Hardware/software technical elements of layers can occur in different
forms. E.g. 7 layers can be realized by inner or outer commands of the operation
system, complemented with network resources, or by task
-
oriented applications, the
4..6 layers can b
e realized by dynamic or static process directories, while the 1..3
layers are realized by driving softwares with BIOS or kernel level, and by the
connecting cards connected with cable.




Building elements of network of the Department


Network of the Dep
artment relies on the NetWare v3.1x of Novell,
and on its
4.1
series network operation system, and on the network
services of the various U
NIX
-
os platform
s

(DEC
-
Alpha, IBM
RS6000, Sun Sparkstation).

Basic model of
Novell
realizes a typical

server/
c
lien
t
co
nnection
, where the server integrates resources
necessary for the laboratory work
(
mass storage devices with fixed
disk, printers, data connection with other servers/networks, etc.)
which are used by PC based workstations with less resources.
HSN laborato
ry of the Department relies on UNIX workstations
with a large capacity, where both the server and the client
applications are used in a given computer. Application of the
M
icrosoft Windows
-
based

(Workgroup)
peer
-
to
-
peer

mode
l is not
typical.

One of the mos
t evident characteristics of network is the accessing
physical connection
, and its topology. It mostly covers the
arrangement of the cable system, the computers, and their network
connecting cards, and other network building elements.
Sematic
draft of the
department network can be seen on Figure 1 (it is the
state of September 1995).


Transmitting data on the physical network is executed according to
largely standardized
protocols
. Protocol levels embedded into each
other provide the access to the data tra
nsmitting medium, the logical
data connection between the intermediate points, and the addressing
and route searching processes, data security and order of
importance, connection between the ends without any error, and the
incidental code conversion for th
e user programs.

Novell

network prefers
IPX/SPX

proto
c
ol
s, but it supports also the
TCP/IP

protocol preferred by UNIX system among others, which

makes possible the connection to the

department computers
(IBM/RISC, DEC/ALPHA, Sun), to department and univ
ersity
computers (Sun, HP/Apollo), to
UNIX laboratories and to the
Internet
.
There are numerous computers at the University, which are
DEC products with a VMS operation system running on them, and
their preferred protocol is
DECNET.
There was an SNA
-
base
d
local network for years in the P
S2 laborat
ory of our Department,
which is the preferred network architecture of the SNA.



5


Figure
1
Sematic draft of the
network of the Department

We can track on the above figure, wh
at kind of basic elements build
the department netwok. In the further part of our material we will
examine the role, the operation, and the test of the individual
elements in details, including the concept of the
repeater,

the

router,
a
nd the

gateway.


Ca
bling


We can classify networks on the basis of the medium used for the
transmission. Here are some
typical

medium, transmission rate and
its connectors
:

Copper cable

S
peed

Tip. Z0

C
onn

Unshielded
-
Twisted
-
Pair,
UTP

10 Mbit/sec*

120



RJ11

RJ45


S桩elded
-
Twisted
-
Pair,
STP

16 Mbit/sec

150


IBM tr


祭metrical c
oa硩a
l

cable

10 Mbit/sec




BNC

Glass fiber




M畬timodal cable pair

150 Mbit/sec

港a

SMA

M畬timodal cable pair

150 Mbit/sec

港a






c
桡湮nl




Wireless LAN,
tra湳missio渠wit栠spreaded
spectr畭

2 Mbit/sec

港a

-

*
I渠t桥 case of
Fast
-
Et桥r湥t
t桥 speed is
100 Mbit/sec!

Nowada祳 t桥

100BaseT is
sta湤ardized.



ble
ㄮ1
Some t祰ical tra湳missio渠medi畭

T桥 fi杵ge below s桯ws t桥

cables

me湴io湥d i渠Table 1,

wit栠t桥ir
co湮nctors



Fi杵ge 2


Cables wit栠co湮nctors


Hereafter we will prese湴 cable t祰es of a 湥twork co湮ncti湧ntool
applied i渠o畲 Departme湴 湯w, or earlier, wit栠a simple error
searc桩湧nprocess.

7

Our Department

prefers the usage of the thin Ethernet cable for
connecting computers. Wave impedance of an

RG58C/U
typed
coaxal cable with an 5
-
mm diameter, and a plastic cover is
50


I湤i癩d畡l parts are 杩癥渠b礠pieces wit栠a BNC pl畧uof t桥ir
e湤s.

O渠Fi杵ge 1 eleme湴s marked as
E渲, E渴, E渶

were impleme湴ed
wit栠t桩s ki湤 of cable t祰e

T桥 cable of
ArcNet
湥twork 畳ed earlier was a c
oa硩
a
l RG62
t祰e,
too, wit栠a wa癥 impeda湣e of
㤵9


We do 湯t alread礠畳e t桩s
t祰e 桥
re at o畲 Departme湴.

Cable of t桥 toke渠ri湧nrealizi湧nt桥 mai渠湥twork of t桥
Departme湴 is a渠IBM
T祰e 1,
w桩c栠桡s a pair of
STP

i渠a m畴畡l
plastic wrap. We ca渠see t桥 ide湴ifier of t桥 Tr5 i渠Fi杵ge 1.


Topolo杹gof cabli湧nca渠be 癡rio畳, as we ca
渠see渠o渠t桥 followi湧n
fi杵ge


Fi杵ge
㌮†
Network topolo杩es

Arrows o渠t桩s fi杵ge i湴e湴 from t桥 tra湳mitti湧n畮ut of o湥
comp畴er to t桥 recei癩湧n畮ut of t桥 ot桥r comp畴er.



For the topology of the track the thin

Ethernet subnetwork segments of the
Department can provide a typical example
(En0, En4, En6
segments on Figure
1
).
Computers can connect to the segment
closed with a

50


of resista湣e o渠its two
e湤s wit栠T forks o渠t桥 bottom of th
e BNC
畮ut of t桥
tra湳cei癥r

of t桥 Et桥r湥t
co湮ncti湧ncard i湳ide t桥m. We ca渠see a
o渠t桥 ri杨g side of t桥 fi杵ge a clos畲e
impleme湴ed i渠a factor礬 w桩le t桥 fi杵ge
below s桯ws a co湮ncti湧npoi湴 wit栠t桥
raised co湮ncti湧ncard.
.


I渠case of a st
art topolo杹gt桥 tra湳mission
-
receptio渠circ畩ts i渠t桥

HUB
畮ut will pro癩de t桥 tra湳missio渠of t桥 si杮gl recei癥d o渠o湥
of t桥 ports to t桥 ot桥rs. I渠case of t桥 older
Arc湥t
湥twork t桥
acti癥 HUB ca渠make a si杮gl re来湥ratio測 too, w桩le t桥 pass
i癥
HUB is a simple circ畩t b畩lt 異 from resista湣es. T桥 moder渠
Fast
-
Et桥r湥t HUB
s ca渠make e癥渠i湴elli来湴 traffic filteri湧ntasks.


Topolo杹gof Toke渠ri湧nrealizi湧nt桥 mai渠湥twork of t桥
Departme湴 is t桥
Star
-
Ri湧n(
it is t桥 Tr5 ri湧ni渠Fi杵ge 1).

MAU
(M畬ti
-
statio渠Access U湩t,
do 湯t mi砠it wit栠termi湯lo杹g湡med
Media Attac桭e湴 U湩t applied i渠
IEEE 802.砠
sta湤ard series
)

pro癩des t桥 sectio湩湧nof a wro湧nor a dead wire comp畴er.

Simple ri湧nis rarel礠applied beca畳e of its poor error
-
tolera湴

abilit礬 w桩le t桥 do畢le ri湧nis a t祰ical topolo杹gof optical
co湮nctio湳 wit栠a lar来 speed.



9

Examination of cables


Operation of local networks is largely influenced by the quality of
cabling. Data traffic can slow down, or can be entirely stopped
because of cable errors.

It refers to that kind of error, if the
number of repetitions or the control text (CRC) errors grow very
fast during the examination with a protocol tester, or with the
examination of the inner counters of an intelligent network t
ool (e.g.
SNMP based monitoring)
.

With the help of the following simple measuring scheme the mosst
types of errors can be exposed easiliy besides locating the place ot
the error. Drawback of this measuring method, that it can be made
only on a section, wh
ich is
free from traffic

(free from energy

Principle of measurement:




Time domain reflection measurement
(TDR)

Tools of measurement
:


-

LeCroy 9450A 300Mhz
o
scillos
cope

-

Justification generator of the oscilloscope, as an impulse
generator

-

A compu
ter connected to the oscilloscope with GPIB for
documentation purposes


Measurable object
:

-

Klf.
(?) cable sections with an error place
induction

Draft of the measuring arrangement
:

Figure
4.
Arrangement of a simple

TDR m
easurement

The task of the Zg c
omplementary element shown on this figure is to
complement the inner impedance of the justification generator to the

nominal impedance of the tested
RG58C/U
cable section.
We can count

the way from the reference point on the side of the generator to the fi
rst

error place (distance of the error place) from t1 time, which is
necessary to the wave front to run this distance from the first error
place and back (reflection).

In the case of the cable in the measuring place the speed of the
wave front is approxim
ately
200000 km/sec (
group speed), which is
smaller, than the speed of the light.

In our case distance can be
estimated with the formula below:

l


t/10

ahol l méterben, t pedig nanoszekundumban van megadva.

Analysing the figure w
ith the oscilloscope we can find several cable
errors.
From
t1

to

t2

the stranger cable section with a larger wave
impedance, at t2 a capacitive endurance at the connection point
(waving!), from t3 it is a normal section, while the end of the cable
is clos
ed with a tear (running up to U0). It is because of the so
many error places, that it cannot reach the U0 of the multiple
reflection

We can see some oscilloscope sheaths belonging to a simple
situation on the line of figures below:
.




11

Tear at
10 m




Sh
ort circuit at

10 m

(
T cstal.
slipped apart
)



(
a crucial
BNC

error, or a
rough breakage)



Reactant endurance at

10m


Norm
a
l
closure at

10m

(
Breakage or a card error
)



Figure
5.
Some typical TDR situations



Examnation of line signals


I
mportant characteristic of a given
LAN
architecture is the method
of a line coding (or perhaps modulation) applying during reception ,
and the electrical methods of the signal (levels, speed).

The two following tables summarize two processes applied in the

case of the LAN of the Department
:

N
ame

S
tandard

S
peed

Coding

Ethernet

IEEE802.3

10Mbit/sec

Manchester

Token
-
Ring

IEEE802.5

16Mbit/sec

Differen
t
i
a
l
Manchester


The following figure shows the beginning of an Ethernet package
on the screen of the oscillo
scope. We can see on the lower ray the
beginning of the frame, as the transmitter switches the impulse flow
levelled

2.05V according to the standard to the cable free fromm
energy.

(
We will see only the
-
1.77 V signal, attenuated by the
cable section in t
he place of the examination.)

We can see on the
upper ray the a part of the lower signal elongated to the 100 nsec
of time base with the 10101011 bit series indicating the beginning
of the frame, at the end of the
preamble
.

Manchester
coding

seen
on the fi
gure is very simple,edge running up at the middle of the bit
time represents the binary one, while the running down one
represents the binary 0. Speed is

10Mbit/sec.


13


Figure
6.
Beginning of an

Ethernet

frame and its electrical
characteristics


On a fa
il
-
safe, but long cable section the signal suffers such a large
attenuation, that won’t be able to a fail
-
safe connection any more.
If, for example, we got at the measuring place packages, where the
signal level reduced under 1 V, we can surely expect to s
low or
wrong operation in the case of a remote workstation.

In this case we must induct
repeater
s,

that operates basically as a
signal generator, and in the case of a more developed tool, as a
traffic filter (which passes through only the traffic from one

section
to the other). This kind of tool with four connection point can be
seen on Figure 1. with an
MPR (
MultiPort repeater
)
mark.

This table below summarizes the maximum length of the cable in the
csase of some Ehternet or token
-
ring cablings, and the
number of
the accessible computers in the case of a passive segment.


Name

Identifier

S
peed

Lenght

Number
of
computer

Thin

Ethernet

10BASE2

10 Mbit/sec

185 m

30

Thick
g Et hernet

10BASE5

10 Mbit/sec

500 m

100

UTP Et hernet

10BASET

10 Mbit/sec

100 m

2,(HU
B)

Fast Ethernet

100BASET

100Mbit/sec

N/A

2 (HUB)

Token ring

Type 1 (STP)

4 Mbit/sec

750 m

260

Token ring

Type 3 (UTP)

4 Mbit/sec

N/A

72





---------------------------------------------------

15


IEEE802
-
es
recommendation series


Examining the bottom o
f the data connection layer of
OSI referenc
e
model
, we can group the various networks according to the method
of the medium access, too.

The four main access methods are
shown in the following table:


On
-
demand

Cont r olled

Cent r ed

Li ne conne ct e d


(PBX)


Pol l i ng

Dis t ribut ed

Random acce s s

(CSMA/CD)

Toke n


I n order t o a mult iple us age of t he given medium we can apply
t i me
-
s hare d, f re que ncy
-
s hare d

or
code
-
s hare d

( e.g. s pr eaded
s pect r um) t r ans mis s ion t echnique.

I n t he cas e of LANs t he
I EEE
r ecor ded in it s

802

recommendation
series some of this kind of methods, including the specifications of
the physical layer, too. They are summarized in the following table:


S
tandard

Subject

OSI
layer

Illustr
ation

IEEE802.2

Logi
cal connection control

2LLC

-

IEEE802.3

C
SMA/CD

2MAC/1

Ethernet

IEEE802.4

Token tracks

2MAC/1

ArcNet

IEEE802.5

Token ring

2MAC/1

IBM Token
-
ring


Hereinafter we will review only the Ethernet process in details,
which is a very preferred application at our Department.

IEEE802.3 (Ethernet
means
a product
!) CSMA/CD (Carrier Sense
Multiple Access with Collision Detection)

is a distributed, on
-
demand, random
-
access medium access method. This standard
recorded six basic functions for the MAC. These are the following:
:

1.

Framing of the transmission d
ata

Preamble
, beginning of frame,
addressing, data embedding, CRC
.

2.

Organization of medium access Receiver perception, switching on
transmitter, impact detection

3.

Data coding




Manchester
coding


4.

Receiver data decoding


Clock signal e
xtraction, frame synch,
Manchester decoding

5.

Reception medium access


Detec
tion
, CRC
control


6.

Un
packing

of received data

Address control, data exposion

Here occurs first the typical basic action of the various protocols,
the
repacking
, which means th
e completion of data packages
arriving from higher protocol levels with incidental information
necessary for the operation of the given level. Figure 7.
demonstrates this activity.

Figure
7.
Framing process of
MAC

Preamble
:


aa

Hex pattern (10101010


bit

s
eries
)
with the length of 7 bytes to the synch o

n the side of the receiver

Frame

start

1 byte
ab

Hex

indicates the beginning of the frame


Task address
:

The 48
-
bit Ethernet address of the

terminal. The
address, which consists of only numeric char
acters “1” is the so
called broadcast, which is a call to every station.


Resource address
:

Address of the transmitting station


Lenght
:


Length of the frame

Data
:


Embedded data from the L
LC.

CRC
-
32


32
-
bit

of controlling amount
.

Since the appearance of
the Ethernet, as a product anticipated the
standardization procedure, there were numerous types of frame
spreaded in practice. One of them is the
"
Ethernet II
", where the
length

information is absent, and instead of it the frame type occurs
derived from th
e higher protocol layers, that is not a really matching
information.
.

What really unified is in this level, that is the distribution of the first
3 maximum byte of the 48
-
bit Ethernet among the varoois vendors.

17

Appendix 1 contains the prefixes assigned
to the different vendors.
E.g. the addresses shown on Figure 7. according to the table refer
to the vendor named

"Western Digital/SMC".


Standard of I
EEE 802.2
specify the method of Logical Link Control
(LLC) of

LAN
s
.
As the standard appeared a bit late,

it was force
to give a start to other product, that have already got a strong place
in the market. This solution is really elegant. In the focus of the
standard a
connection
-
oriented

standard, the so called number 2
tries to
fit in the OSI reference model
, while the number 1
connection free

protocol means the start,

where there is no really
protocol in special cases, the layer is quasi transparent towards the
upper, not OSI layers.


In the case of the connection free protocol there is no frame
numbering a
nd error protection


these are the tasks of the higher
protocol levels.

We will not review the connection
-
oriented case, in details, since
the LAN of the Department does not apply this one. Instead of it we

demonstrate the summary of frame types occurrin
g at our
Department in practice, complemented with the LLC information
fields.

Byte

Ethernet II

Ethernet
-
SNAP

IEEE802.3

IEEE802.2

0
-
5

Task address

Task address

Task address

Task address

6
-
11

Resource
address

Resource
address

Resource
address

Resource ad
dress


Type

Lengt h

Lengt h

Lengt h

14


D
SAP


D
SAP

15


S
SAP


S
SAP

16


Control


Control
-
1

17


Organization


(Control
-
2)

18


Code



19


(3 byte)



20
-
21



Type




The start giving mentioned above can manifest itself in the case of
the
802.2,
and

SNA
P

preferred by IBM, that the
operation code

of the connection free LLC corresponds to the sending of a plain
information without any numbering

(
Control

field,
Unnumbered
Info,
code:
03)

at the transmission of
Novell
and

TCP/IP proto
c
ol
s.

As an illustratio
n, the table below shows some connection free
codes in the case of
802.2
and

IBM
framing.
.

Type
1.LLC
operation

802.2 Control

IBM Control

Unnumbered

Info. (UI)

C0

03

Change of ident ifier
(XID)

F5

AF

TEST

C7

E3


19

Type identifiers
(
Type

field)
are current

in practice, they identify
protocols of firms producting various LAN solutions, or “self
-
employed” protocols of organizations


their list can be found in
Appendix 2


SAP

(Service Access Point
)

provides theoretically virtual
connection points to the netwo
rk layer for the access of the
individual network services, but in practice it serves for the
indentification of higher level or embedded protcols


as it is shown
in the table below.

00

Management

02

Individual LLC sublayer management

03

Group LLC
sublayer management

04

SNA Path Control

06

Internet IP

0E

Proway
-
LAN

42

Spanning tree

4E

EIA
-
RS 511

5E

ISI IP

80

3Com XNS

8E

Proway
-
LAN

AA

TCP/IP SNAP

(Ethernet type in LLC)

BC

Banyan VINES

E0

Novell IPX

F0

IBM NetBIOS

F4

IBM LAN
Management

FC

RPL

FE

ISO DIS 8473

FF

Broadcast


In the case of the

IPX
/SPX protocol of the

Novell Netware either
the resource
(Source SAP, SSAP)

or the task
(Destination SAP,
DSAP)
code is
E0
.
In case of the
Internet
traffic of the Tr5 ring
seen on

Figure 1 this code will be
AA
.



The

SIEMENS K1102
typed

LAN proto
c
ol

tester


SIEMENS K1102 dual
-
port proto
c
ol

analysa
tor
is suitable for the
examination of local
(LAN),
and large
(WAN)
netoworks, with
application of optionally changeable interface types

-

IEEE802.3
(Ethernet), IEEE802.4 Token
-
Bus, IEEE802.5 Token
-
Ring, FDDI,
and
V11/V28 WAN.

The specimen in the laboratory has only
IEEE802.3
and

V28/V11
measuring interfaces.

The protocol tester has
an
independent t
ransmission (traffic
generator) and recei
ver (analysator) function, separatedly for both
two ports, thus it is suitable for the examination of network routers
and gateways.

Its measuring interfaces are different from the normal network
connection tools in several points.


-

More

developed clock signal
extraction and sycnh


-

Filter functions with a transputer


-

Large, quick storage for longer registrated issues


-

A possibility for a direct data change between the two interfaces




Block diagram of the hardware protocol tester:



AT
-
bus


¦ +
--
AT
-
CPU
----
+


¦ ¦ +
--

billentyûzet



¦
---
¦ AT
-
alaplap ¦


¦ ¦ processzor +
--

printer


¦ ¦ ¦


¦ +
------------
+


+
------------
+ +
------------
+ ¦ +
--
DISPLAY
---
+


¦ 1.sz mérõ ¦ ¦ Transputer ¦ ¦ ¦ EGA ¦ EL
-
EGA


LAN1
-
><
--
¦ interfész ¦
--
¦ + RAM ¦
--
+
---
¦ csatoló +
--

display


¦ és csatl. ¦ ¦ (+Filter) ¦

¦ ¦ kártya ¦


+
------------
+ +
------------
+ ¦ +
------------
+


¦ ¦ +
------------
+ ¦ +
------------
+ +
------
+


¦ +
---
¦ Ütemezés, ¦ ¦ ¦ Floppy disk¦ ¦Floppy¦


Adatcsere

¦ órajel ¦ ¦
---
¦ kontroller +
-
¦disk ¦


¦ +
---
¦ kinyerés ¦ ¦ ¦ ¦ ¦drive ¦


¦ ¦ +
------------
+ ¦ +
------------
+ +
------
+


+
------------
+ +
------------
+ ¦ +
------------
+ +
------
+


¦ 2.sz
mérő

¦ ¦ Transputer ¦ ¦ ¦ Hard disk ¦ ¦Hard ¦


LAN2
-
><
--
¦ interfész ¦
--
¦ + RAM ¦
--
+
---
¦ kontroller +
-
¦disk ¦


¦ és csatl. ¦ ¦ (+Filter) ¦ ¦ ¦ ¦ ¦drive ¦


+
------------
+ +
------------
+ ¦ +
------------
+ +
------
+


¦ +
------------
+


¦ ¦ szabad ¦


¦
---
¦ SLOT(ok) ¦



¦ ¦

21


+
------------
+


The
module of the protocol tester event and the data extractor
consist of the
interface connector and the transputer card

The
examined amount o
f data can be reduced by installing a hardware
levelled filtering function.

The protocol tester has a built
-
in tool ensuring the man
-
machine
connection (keyboard, display),
a mass storage device
(Floppy,
Hard disk, RAM),

and recording tools

(printer, disk
).
These
functions can operate with the help of a built
-
in
IBM
-
PC/AT
compatible computer.

The basic operation system is the
DOS 4.0,

and the makers of this
tool prepared numerous applications for this.


There are two
program packages in the computer, a on
e
-
port Ethernet analysator
package from 1992, and a dual
-
port from 1993, where one of the
supported interfaces is the Ethernet.
.

The one
-
port
(SP)
package
(c:
\
k1102etn
subdirectory
)
consists of
four elements
:



* K1102I
frame program
(shell)




* K1102AI standard test
s


-

Node detection


-

Proto
c
ol dete
ction


-

Examination of the
ISO transport

layer


-

Echo test



* K1102DI diagnos
t
i
c


-

Frame r
ecording


-

Traffic generation from stored
frame
s


-


Generate Network Load


-

Program
med measures

(
Received event
-
>frame s
ending
)



* K1102SI
preparation of statistics


-

L
oad trend


-

Collision trend


-

Fault trend


-

Length distr
ibution


-

Gap distribution


-

Fault distribution


-

Load distribution according to stati
ons


-

Display of connection matrix



The dual
-
port

(DP)
package

(c:
\
k1102dp
subdirectory

k1102.exe)

makes possible the operation of the basic functions mentioned
above at the same time besides a multiple window display, where
the same o
r different results of one, or both ports

can be displayed
in two windows.

23

The protocol tester at the measuring place has a special
configuration, because it was completed with a NE2000 compatible
Ethernet connecting card for documentation purposes, and

with the
necessary softwares for the access to the Novell network.

The following figure shows the arrangement of the measuring place
in the LAN environment of the Department.
.



Figure
8.
Fitting of the measuring place to the LAN of the
Department


Th
e measurable object in the case of monitoring will be the
living
traffic

of the thin Ehternet segment marked as En2 (logically it is
the main network of the Stoczek building), while in the case of
traffic generation we should use the En4 segment after the
change of
the two connecting points.

After switching the tester on, students can enter automatically to the
Novell network of the Department, which makes possible the
storage of measurement results on the students’ workplaces (HOME
or PROJECT).

As a res
ident, there will be loaded a
screen

image storing program
named CAMERA, which
makes possible the recording of the
graphic screen images of the tester in a file of LBM format. After
pressing the
ALT+C
keyboard combination
SCREENnn.LBM file
s
are generated,
where

nn

is the number of the picture. These can be
converted with the help of the
CONVERT program
to a PCX format

appropriate for the
Word.


One of the services of the tester is to record some of the results to
files. We will review the files applied by th
e tester in the next
chapter in details
.

25

Databases of the
K1102


During the examination of the local networks the various data
structures have an important role, especially the set of the protocol
elements, the storage of the measuring results, and the li
sts applied
during the operation of the network, which contain the data of
computers of LAN.

In the case of

K1102
a separated menu can be found for handling of
the various database files, and for their selection
(System
Management
-
File Management).

Figur
e
9.
Databases of
K1102

Perhaps there will be necessary for us to introduce
filtering
conditions

during the analysis of the traffic, if we wish to narrow
the range of our examinations e.g. for a grup of computers (filtering
according to the address), or

for a kind of protocol, or for the
combination of these ones. The filtering conditions, which can be
set under the

"Presetting
-
Harware filter" menu, can be stored in files
of
*.FIL

format.


Figure
10.
Setting of filtering conditiions

27

On the previous we
can see an example, where we narrow the
resource address to SMC/WD type of connection cards, and we
want to see only Novell packages with Ethernet II.
(Novell old,
Type 8137
in the
Area
field)
.

We can set more of these kind of records, but we can activate
only
six
during one measurement. The tester contains more filters set in
advance (in USER or ROOT directories), some typical filters from
them:

DUR_IP.FIL


Internet IP
packages

DUR_NOV.FIL


Novell IPX/SPX

DUR_BANY.FIL


Banyan Vines

During
traffic generati
on

or programmed measurement perhaps
there will be necessary
to set the content of packages to be sent for
simulation purposes. Tester stores this kind of set of packages in
files of
*.GEN

format. Compilation of content of the chosen file can
be executed i
n the
"Presetting
-

Transmit frames" m
enu, giving the
frame fields learnt at the filters, and the content of the package.

If later we would like to store one part of the traffic for processing
purposes (Evaluation menu
)
, the tester will put the content of

the
hardware filtered packages into
*.DAT

file
s
.

Definition of the content of packages
(Evaluation
-

Frame decoding
menü)
can be made easier with
*.NRM
files given the names of the
individual protocol
-
dependent fields and their positions in the frame.
The
re is an appropriate file at the most frequent protocols disposal.
If we want to examine a special protocol (protocol developint
work), we can generate the NRM file with the help of the enclosed

SLD/PR

translator
.


We have also a SPZ specification belong
ing to the manufactured
NRMs.

Here is a detail from the
TCP/IP specifi
cation
:

Link ::= PSDL_SEQUENCE {


destination

Link_addr,


source

Link_addr,



type

Type }

Link_addr ::= BYTE_HEX {LENGTH(6) STATION}

Type ::= BYTE_HEX {LENGTH(2) COMMENT(


['
0800
'H]
"
internet
",



['
0806
'H] "
arp
",


"not_internet")}


*.DBF

(DBase III format) of the DP program package, and
*.STA

database of the SP package serve for the registration of nodes of

the local network by name. It is very useful, if the individual nodes
appear according to their names at the maintenance activities of the
network, at error searching, and at preparation of statistics and
distributions, and we can thus refer to their name
s.

We can edit the list of stations in the

"Sytem management
-

Node
list" men
u
.


Fortunately, the
DBF form
a
t

is quite frequent, so, for example even
the
Microsoft
-
Excel
can handle it directly. It is worth
to con
vert for the programs of the
SP
package to the
STA form
at with the help of the

"File management
-

Select file
-

transfer" men
u.

During

the monitoring of the network

we can store
the results in
*.MON

file
s It can b
e evaluated later
according to various points of views
(Evaluation men
u
),

or it can be
converted for other table handling programs

(MON2DBF men
u
).

E.g. distribution of a traffic
statistics related to computers can make in a circle
diagram format with a l
ink of processes of

MON2D
BF
-

Excel import
-

Excel chart.





29

Mandatory literature


BME
-
TTT, Segédlet a "Lokális számítógéphálózatok szolgáltatásai" c.
méréshez, 1995

N:
\
MERESEK
\
05
\
DOC
\
?????.DOC


BME
-
TTT, Segédlet az "Elektronikus Levelezés" c. méréshez, 19
94

N:
\
MERESEK
\
??
\
DOC
\
EMAIL.DOC


Recommended literature


James Martin, Kathleen K. Chapman: LOKÁLIS HÁLÓZATOK

NOVOTRADE Kiadó kft.
-
Prentice Hall, 1992


Andrew S. Tanenbaum: SZÁMÍTÓGÉP
-
HÁLÓZATOK

NOVOTRADE Kiadó kft.
-
Prentice Hall, 1992


Dr. Harangozó József
: Számítógéphálózati laboratóriumi gyakorlatok

BME
-
Folyamatszabályozási Tanszék, 1994


SIEMENS Ag.: K1102 LAN Protocol Tester, User Manual,

Order No.: C73000
-
G6076
-
C200, 1991 április





Appendix
1
.

Ethernet Vendor
codes




00
-
00
-
02

BBN

00
-
00
-
0C

Cisco

00
-
00
-
0E

Fujitsu

00
-
00
-
0F

NeXT

00
-
00
-
10

Sytek/Hughes LAN Systems

00
-
00
-
11

Tektronics

00
-
00
-
15

Datapoint

00
-
00
-
18

Webster

00
-
00
-
1A

AMD ?

00
-
00
-
1B

Novell/Eagle Technology

00
-
00
-
1D

Cabletron

00
-
00
-
20

Data Industrier AB

00
-
00
-
21

SC&C

00
-
00
-
22

Visual Tech
nology

00
-
00
-
23

ABB

00
-
00
-
29

IMC

00
-
00
-
2A

TRW

00
-
00
-
3C

Auspex

00
-
00
-
3D

ATT

00
-
00
-
44

Castelle

00
-
00
-
46

Bunker Ramo

00
-
00
-
49

Apricot

00
-
00
-
4B

APT

00
-
00
-
4F

Logicraft

00
-
00
-
51

Hob Electronic

00
-
00
-
52

ODS

00
-
00
-
55

AT&T

00
-
00
-
5A

SK/Xerox

00
-
00
-
5D

RCE

00
-
00
-
5E

IANA

00
-
00
-
61

Gateway

00
-
00
-
62

Honeywell

00
-
00
-
65

Network General

00
-
00
-
69

Silicon Graphics

00
-
00
-
6B

MIPS

00
-
00
-
6E

Artisoft

00
-
00
-
77

MIPS/Interphase

00
-
00
-
78

Labtam

00
-
00
-
7A

Ardent

00
-
00
-
7B

Research Machines

00
-
00
-
7D

Cray Research/Harris

00
-
00
-
7F

Linotronic

00
-
00
-
80

Dowty Network Services

00
-
00
-
81

Synoptics

00
-
00
-
84

Aquila ?

00
-
00
-
86

Gateway

00
-
00
-
89

Cayman Systems

00
-
00
-
8A

Datahouse Information
Systems

00
-
00
-
93

Proteon

00
-
00
-
94

Asante

00
-
00
-
95

Sony/Tektronics

00
-
00
-
97

Epoch

00
-
00
-
98

Cros
sCom

00
-
00
-
9F

Ameristar Technology

00
-
00
-
A0

Sanyo Electronics

00
-
00
-
A2

Wellfleet

00
-
00
-
A3

NAT

00
-
00
-
A4

Acorn

00
-
00
-
A5

Compatible Systems
Corporation

00
-
00
-
A6

Network General

31

00
-
00
-
A7

NCD

00
-
00
-
A8

Stratus

00
-
00
-
A9

Network Systems

00
-
00
-
AA

Xerox

00
-
00
-
C0

Western Digital/SMC

00
-
00
-
C9

Emulex

00
-
08
-
2D

Siemens Nixdorf: TACLAN

00
-
AA
-
00

Intel

00
-
DD
-
00

Ungermann
-
Bass

00
-
DD
-
01

Ungermann
-
Bass

02
-
07
-
01

MICOM/Interlan

02
-
60
-
8C

3Com

08
-
00
-
02

3Com
-
Bridge

08
-
00
-
05

Symbolics

08
-
00
-
06

Siemens Nixdorf

08
-
00
-
07

Appl
e

08
-
00
-
09

HP

08
-
00
-
0A

Nestar Systems

08
-
00
-
0B

Unisys

08
-
00
-
10

AT&T

08
-
00
-
11

Tektronics

08
-
00
-
14

Excelan

08
-
00
-
20

Sun

08
-
00
-
2B

DEC

08
-
00
-
38

Bull

08
-
00
-
39

Spider

08
-
00
-
46

Sony

08
-
00
-
4E

BICC

08
-
00
-
5A

IBM

08
-
00
-
69

Silicon Graphics

08
-
00
-
6E

Excelan

08
-
00
-
7C

Vitalink

08
-
00
-
89

Kinetics

08
-
00
-
90

Retix




Apppendix
2.

Codes of the
Ethernet Type
field


0600

XNS

0601

XNS Address Translation

0800

DOD IP

0801

X.75 internet

0802

NBS internet

0803

ECMA internet

0804

Chaosnet

0805

X.25 Level 3

0806

ARP

0807

XNS Compatibility

081C

Symbolics private

0888
-

Xyplex

0900

Ungermann
-
Bass net debug

0A00

Xerox PUP

0A01

Xerox PUP Address Translation

0BAD

Banyan Systems

0BAF

Banyan Echo

1000

Berkeley trailer negotiation

1001
-

Berkeley trailer encapsulation

1234

DCA
-

Multicast

1600

VALID system protocol

1989

Artificial Horizons (dogfight
sim.)

3C00
-

3Com NBP

4242

PCS Basic Block Protocol

4321

THD
-

Diddle

5208

BBN Simnet Private

6000

DNA experimental

6001

DNA Dump/Load
-
MOP
-

6002

DNA Remote Console
-
MOP
-

6003

DN
A IV Routing Layer

6004

DEC: Local Area Transport

6005

DEC: Diagnostics

6006

DEC: Customer Use

6007

DEC: LAVC

6010
-

3Com

7000

Ungermann
-
Bass download

7001

Ungermann
-
Bass NIUs

7002

Ungermann
-
Bass
diagnostic/loopback

7003

Ungermann
-
Bass

7005

Ungermann
-
B
ass Bridge

7007

OS/9 Microware

7009

OS/9 Net ?

7020
-

Sintrom (was LRT)

7030

Racal
-
Interlan

7031

Prime NTS

7034

Cabletron

8003

Cronus VLN

8004

Cronus Direct

8005

HP Probe

8006

Nestar

8008

AT&T/Standford

8010

Excelan

8013

Silicon Graphics diagnostic

8
014

Silicon Graphics network games

8015

Silicon Graphics

8016

Silicon Graphics XNS Nameserver

8019

Apollo DOMAIN

802E

Tymshare

802F

Tigan

8035

Reverse ARP

8036

Aeonic Systems

8037

IPX (Netware)

8038

DEC: bridge

8039

DEC: DSM/DDP

803A

DEC: (Argonaut c
onsole)

803B

DEC: (VAXELN)

803C

DEC: NMSV DNA Naming

803D

DEC: encryption

803E

DEC: distributed time service

803F

DEC: LAN Traffic Monitor

8040

DEC: NetBIOS Datagrams

8041

DEC: Local Area System Transport

8042

DEC Unassigned

8044

Planning Research Corp
.

8046
-

AT&T

8048

DEC: DECamds

8049

ExperData

805B

VMTP/RFC
-
1045

805C

Stanford V Kernel

805D

Evans & Sutherland

8060

Little Machine

8062

Counterpoint Computers

8065
-

UMass. at Amherst

8067

Veeco Integrated Automation

8068

General Dynamics

8069

AT&T

806A

Autophon

806C

ComDesign

806D

Compugraphic Corp.

806E
-

Landmark Graphics Corp.

807A

Matra

807B

Dansk Data Elektronic

807C

Merit Internodal

807D
-

Vitalink Communications

8080

Vitalink TransLAN III Mgmt

8081
-

Counterpoint Computers

8088
-

Xyplex

809B

AppleTalk (EtherTalk)

33

809C
-

Datability

809F

Spider Systems

80A3
-

Siemens
-
Nixdorf

80C0
-

DCA: Data Exchange Cluster

80C6

Pacer Software

80C7

Appplitek Corp.

80C8
-

Intergraph Corp.

80CD
-

Harris Corporation

80CF
-

Taylor Instrument

80D3
-

Rosemount Corp.

80D5

IBM SNA Service on Ethernet

80DD

Varian Associates

80DE
-

TRFS (Integrated Solutions)

80E0
-

Allen
-
Bradley

80E4
-

Datability

80F2

Retix

80F3

AppleTalk AARP

80F4

Kinetics

80F7

Apollo Computers

80FF
-

Wellfleet

8107
-

Symbolics

812B

Talaris

8130

Water
loo Microsystems

8131

VG Laboratory Systems

8137

Novell NetWare

8139
-

KTI

814C

SNMP over Ethernet

814F

Technically Elite Concepts

817D

XTP

81D6

Lantastic

8582

Kalpana



8888

HP LanProb

9000

Loopback

9001

3Com: XNS Mngmt

9002

3Com: TCP/IP Mngmt

9003

3Com: loopback detection

AAAA

DECNET

FF00

BBN VITAL
-
LanBridge