ADDERLink INFINITY Manual

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Forwarding modes
In	essence,	the	job	of	a	layer	2	switch	is	to	
transfer as fast as possible, data packets arriving 
at one port out to another port as determined 
by the destination address. This is known as data 
forwarding and most switches offer a choice 
of methods to achieve this. Choosing the most 
appropriate forwarding method can often have a 
sizeable impact on the overall speed of switching:
•	Store and forward is the original method 
and requires the switch to save each entire 
data packet to buffer memory, run an error 
check and then forward if no error is found (or 
otherwise discard it).
•	Cut-through was developed to address 
the latency issues suffered by some store 
and forward switches. The switch begins 
interpreting each data packet as it arrives. 
Once	the	initial	addressing	information	has	
been read, the switch immediately begins 
forwarding the data packet while the remainder 
is	still	arriving.	Once	all	of	the	packet	has	been	
received, an error check is performed and, if 
necessary, the packet is tagged as being in 
error.	This	checking	‘on-the-fly’	means	that	cut-
through switches cannot discard faulty packets 
themselves. However, on receipt of the marked 
packet, a host will carry out the discard process.     
•	Fragment-free is a hybrid of the above two 
methods.	It	waits	until	the	first	64	bits	have	
been received before beginning to forward 
each data packet. This way the switch is more 
likely to locate and discard faulty packets that 
are fragmented due to collisions with other 
data packets.  
•	Adaptive switches automatically choose 
between the above methods. Usually they start 
out as a cut-through switches and change to 
store and forward or fragment-free methods 
if large number of errors or collisions are 
detected. 
So which one to choose? The Cut-through method 
has the least latency so is usually the best to use 
with AdderLink Infinity units. However, if the 
network components and/or cabling generate a lot 
of errors, the Store and forward method should 
probably	be	used.	On	higher	end	store	and	forward	
switches, latency is rarely an issue.
Layer 2 and Layer 3: The OSI model
When discussing network switches, the terms 
Layer	2	and	Layer	3	are	very	often	used.	These	
refer	to	parts	of	the	Open	System	Interconnection	
(OSI)	model,	a	standardised	way	to	categorise	the	
necessary functions of any standard network. 
There	are	seven	layers	in	the	OSI	model	and	these	
define the steps needed to get the data created by 
you	(imagine	that	you	are	Layer	8)	reliably	down	
LAYER 7LAYER 7
LA YER 
6LAYER 6
LA YER 
5LAYER 5
LA YER 
4LAYER 4
LA YER 
3LAYER 3
LA YER 
2LAYER 2
LA YER 
1LAYER 1
Application
Presentation
Session
Tr
anspor t
Network
Data Link
Physical
Network connection
So	why	are	Layer	2	and	Layer	3	of	particular	
importance when discussing AdderLink Infinity? 
Because the successful transmission of data relies 
upon fast and reliable passage through network 
switches – and most of these operate at either 
Layer	2	or	Layer	3.
The job of any network switch is to receive each 
incoming network packet, strip away only the first 
few wrappers to discover the intended destination 
then rewrap the packet and send it in the correct 
direction. 
In simplified terms, the wrapper that is added 
at	Layer	2	(by	the	sending	system)	includes	the	
physical address of the intended recipient system, 
i.e. the unique MAC address (for example, 
09:f8:33:d7:66:12)	that	is	assigned	to	every	
networking device at manufacture. Deciphering 
recipients at this level is more straightforward 
than at Layer 3, where the address of the recipient 
is represented by a logical IP address (e.g. 
192.168.0.10)	and	requires	greater	knowledge	
of the surrounding network structure. Due to 
their more complex circuitry, Layer 3 switches are 
more	expensive	than	Layer	2	switches	of	a	similar	
build quality and are used more sparingly within 
installations.
onto the transmission medium (the cable, optical 
fibre, radio wave, etc.) that carries the data to 
another user; to complete the picture, consider the 
transmission	medium	is	Layer	0.	In	general,	think	of	
the functions carried out by the layers at the top as 
being complex, becoming less complex as you go 
lower down. 
As your data travel down from you towards 
the transmission medium (the cable), they are 
successively encapsulated at each layer within a 
new wrapper (along with a few instructions), ready 
for	transport.	Once	transmission	has	been	made	
to the intended destination, the reverse occurs: 
Each wrapper is stripped away and the instructions 
examined until finally only the original data are left.   
						

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ALIF 1000 general specifications
Casing	(w	x	h	x	d):		 198mm	(7.92”)	x	44mm	(1.76”)	x	120mm	(4.8”)
Construction:		 1U	compact	case,	robust	metal	design	
Weight:		 	 0.75kg	(1.65lbs)
Mount	kits:		 	 Rack	mount	-	single	or	dual	units	per	1U	slot.
     VESA monitor / wall mount chassis.
Power	to	adapter:		 100-240VAC	50/60Hz,	0.5A,	
Power	to	unit:	 5VDC	12.5W
Operating	temp:		 0ºC	to	40ºC	(32ºF	to	104ºF)
Approvals:    CE, FCC
ALIF 2000 general specifications
Casing	(w	x	h	x	d):		 198mm	(7.92”)	x	44mm	(1.76”)	x	145mm	(5.7”)
Construction:		 1U	compact	case,	robust	metal	design	
Weight:		 	 1.11kg	(2.44lbs)
Mount	kits:		 	 Rack	mount	-	single	or	dual	units	per	1U	slot.
     VESA monitor / wall mount chassis.
Power	to	adapter:		 100-240VAC	50/60Hz,	0.8A,	
Power	to	unit:	 5VDC	20W
Operating	temp:		 0ºC	to	40ºC	(32ºF	to	104ºF)
Approvals:    CE, FCC
9pin D-type  female9pin D-type female
11DCD DCD
22RXDRXD
33TXDTXD
44DTRDTR
55GNDGND
66DSRDSR
77RTSRTS
88CTSCTS
Supported video modes
ALIF units support all VESA and CEA video modes.
RS232 ‘null-modem’ cable pin-out
Appendix D   
						

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Appendix E
Fibre modules and cables (ALIF 2000 units only) 
To	suit	your	installation	layout,	two	fibre	modules	are	available	for	the	ALIF	2000	
units to suit various fibre optic cables. The specifications for all\
 are summarised in 
the table below:   
Fibre TypeFibre size Fibre Type Colour CodeDistance  
at	1Gbps
Adder part 
number for 
SFP module
Bar  
colour
Conn.  
type
 Normal Applications Military Applications Suggested Print Nomenclature
OM1(62.5/125)	Multimode  
(TIA-492AAAA)
	Orange Slate	62.5/125220mSFP-MM-LCBlackLC
OM2(50/125)Multimode   
(TIA-492AAAB)	
	Orange	Orange	50/125550m“““
OM3(50/125)Multimode  
(850	nm	Laser-optimised)	 
(TIA-492AAAC)	
 Aqua Undefined		850	LO	50	/125550m“““
OM4(50/125)Multimode   
(850	nm	Laser-optimised)	 
(TIA-492AAAC)	
 Aqua Undefined		850	LO	50	/125550m	“““
OS1	and	OS2(9/125)Single-mode  
(TIA-492C000	/	TIA-492E000)
 Yellow Yellow SM/NZDS, SM10KmSFP-SM-LCBlueLC   
						

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Appendix F
Additional features available on ALIF2002T
New lossless CODEC (AFZ) ALIF 2002T only
The new compression scheme builds on the existing codec and is primarily\
 
focused	on	improving	the	performance	for	“natural”	images	(i.e.	photographs	
and movies). It works in concert with the existing codec and is automat\
ically 
selected whenever there is a benefit to do so.
The new codec is lossless and is very low latency (a small fraction of \
a frame 
delay).	It	generally	achieves	50%	improvement	(in	compression)	over	the	current	
scheme for any areas of the screen that consist of images, gradients, sh\
adows 
etc., elements commonly found in modern desktop environments.
To maintain compatibility with non AFZ -enabled transmitters and receive\
rs 
there is an automatic switching method which will revert back to RLE whe\
n an 
AdderLink Infinity receiver is connected to the AdderLink Infinity D\
ual.
Magic Eye (anti-dither support added) ALIF 2002T only
This is enabled by default.
The Magic Eye feature increases performance and reduces network traffi\
c when 
the AdderLink Infinity Dual is used with Apple Macs and other host com\
puters 
that have dithered video output. It also improves performance if the vid\
eo 
source	is	noisy	(e.g.	from	a	VGA-to-DVI	converter).
Dithering is a technique used by some graphics cards to improve perceive\
d 
image quality by continuously varying the colour of each pixel slightly.\
 This gives 
the illusion of more shades of colour than the display can really reprod\
uce, and 
smooths the appearance of gradually shaded areas in images. Unfortunatel\
y 
dithering	is	an	issue	for	KVM	extenders	such	as	AdderLink	Infinity	because	it	
makes the image appear to be changing all the time even when it is stati\
c, thus 
creating	much	more	network	data	than	can	be	carried	by	a	Gigabit	Ethernet.	
The result is a reduction in video frame rate, which the user sees as sl\
ow mouse 
response.
Magic Eye works by ignoring small variations in the video from frame to \
frame. 
It is enabled by default as it is not obvious to the user that his poor \
mouse 
behaviour is caused by dithering. In most cases Magic Eye is invisible, \
but it 
can produce slight colour inaccuracies on the monitor. For full colour a\
ccuracy, 
Magic Eye can be disabled for video sources which are not dithered or no\
isy.   
						

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Warranty
Adder Technology Ltd warrants that this product shall be free from defects in 
workmanship and materials for a period of two years from the date of ori\
ginal 
purchase. If the product should fail to operate correctly in normal use \
during the 
warranty period, Adder will replace or repair it free of charge. No liab\
ility can be 
accepted for damage due to misuse or circumstances outside Adder’s co\
ntrol. 
Also Adder will not be responsible for any loss, damage or injury arisin\
g directly 
or indirectly from the use of this product. Adder’s total liability u\
nder the terms 
of this warranty shall in all circumstances be limited to the replacemen\
t value of 
this product.
If any difficulty is experienced in the installation or use of this pr\
oduct that you 
are unable to resolve, please contact your supplier.
Safety information
•	 For	use	in	dry,	oil	free	indoor	environments	only.
•	 Warning	-	live	parts	contained	within	power	adapter.
•	 No	user	serviceable	parts	within	power	adapter	-	do	not	dismantle.
•	Plug the power adapter into a socket outlet close to the module that it \
is 
powering.
•	Replace the power adapter with a manufacturer approved type only. 
•	Do not use the power adapter if the power adapter case becomes damaged, \
cracked or broken or if you suspect that it is not operating properly.
•	If you use a power extension cord with the units, make sure the total 
ampere rating of the devices plugged into the extension cord does not 
exceed the cord’s ampere rating. Also, make sure that the total amper\
e 
rating of all the devices plugged into the wall outlet does not exceed t\
he 
wall outlet’s ampere rating.
•	Do not attempt to service the units yourself.   
						

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Radio Frequency Energy
A Category 5 (or better) twisted pair cable must be used to connect th\
e units in 
order to maintain compliance with radio frequency energy emission regula\
tions 
and ensure a suitably high level of immunity to electromagnetic disturba\
nces.
All other interface cables used with this equipment must be shielded in \
order 
to maintain compliance with radio frequency energy emission regulations \
and 
ensure a suitably high level of immunity to electromagnetic disturbances\
.
European EMC directive 2004/108/EC
This equipment has been tested and found to comply with the limits for a\
 class 
A computing device in accordance with the specifications in the Europe\
an 
standard	EN55022.	These	limits	are	designed	to	provide	reasonable	protection	
against harmful interference. This equipment generates, uses and can rad\
iate 
radio frequency energy and if not installed and used in accordance with \
the 
instructions may cause harmful interference to radio or television recep\
tion. 
However, there is no guarantee that harmful interference will not occur \
in a 
particular installation. If this equipment does cause interference to ra\
dio or 
television reception, which can be determined by turning the equipment o\
n 
and off, the user is encouraged to correct the interference with one or \
more 
of the following measures: (a) Reorient or relocate the receiving ante\
nna. (b) 
Increase the separation between the equipment and the receiver. (c) Co\
nnect 
the equipment to an outlet on a circuit different from that to which the\
 receiver 
is connected. (d) Consult the supplier or an experienced radio/TV tech\
nician for 
help. 
FCC Compliance Statement (United States)
This equipment generates, uses and can radiate radio frequency energy 
and if not installed and used properly, that is, in strict accordance wi\
th the 
manufacturer’s instructions, may cause interference to radio communic\
ation. 
It has been tested and found to comply with the limits for a class A com\
puting 
device	in	accordance	with	the	specifications	in	Subpart	J	of	part	15	of	FCC	rules,	
which are designed to provide reasonable protection against such interfe\
rence 
when	the	equipment	is	operated	in	a	commercial	environment.	Operation	of	this	
equipment in a residential area may cause interference, in which case th\
e user at 
his own expense will be required to take whatever measures may be necess\
ary 
to correct the interference. Changes or modifications not expressly ap\
proved by 
the manufacturer could void the user’s authority to operate the equip\
ment.
Canadian Department of Communications RFI statement
This equipment does not exceed the class A limits for radio noise emissi\
ons from 
digital apparatus set out in the radio interference regulations of the C\
anadian 
Department of Communications.
Le présent appareil numérique n’émet pas de bruits radioé\
lectriques dépassant 
les limites applicables aux appareils numériques de la classe A presc\
rites dans 
le règlement sur le brouillage radioélectriques publié par le m\
inistère des 
Communications du Canada.   
						

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www.ctxd.com Documentation by:
©	2013	Adder	Technology	Limited
All trademarks are acknowledged.
Part	No.	MAN-ALIF	•	Release	2.3d
Web:  www.adder.com
Contact:  www.adder.com/contact-details
Support: forum.adder.com   
						

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HT
Index
A
Adaptive		30
AFZ  33
ALIF2002T		33
Anti-dither support  33
B
Background	Refresh		29
Bracket
rack	mount		8
Brackets
fitting		8
Browser-based	utility		20
C
Cable spec
null	modem		25
CODEC		33
Colour	Depth		29
Configuration
browser-based	utility		20
styles		2
Connections
network	link		14
overview  9
RX	audio		16
RX	AUX	port		17
RX	power	in		18
RX	USB	devices		17
RX	video	display		15
TX	audio	links		11
TX	AUX	port		12
TX	power	in		13
TX	USB	link		12
TX	video	link		10
Connectors
overview  3,4
Cut-through		30
D
Dimensions		31
F
Factory	reset		19
Fast-Leave		28
Firmware
upgrade		21
Forwarding	modes		30
Fragment-free		30
Frame	Skipping		29
Front panel  3,4
Front	panel	indicators		22
I
IGMP		28
fast-leave		28
querier		28
snooping		28
Indicators		3,4,22
Initial	configuration		19
J
Jumbo	frames	(packets)		28
L
Layers	2	and	3		30
M
Magic Eye  33
N
Network	layout		24
Network switch
choosing		24
Null-modem cable
pin-out		31
O
OSI	model		30
P
Parts
optional  7
supplied		5,6
Peak	Bandwidth	Limiter		29
Q
Querier		28
R
Rack	mounting		8
Rear panel  3,4
Reset
manual		19
S
Safety information  34
Snooping		28
Spanning	Tree	Protocol		29
Specifications		31
Store	and	forward		30
Switch
choosing		24
configuring		25
T
Troubleshooting		23,26
U
Upgrade
firmware		21
V
Video	modes		31
Video	settings		29
W
Warranty  34
Weight		31