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1. Functional description
The 10/100BASE-T(X) ports of an RS2-…/…
represent a terminal connection for the
connected LAN segment. You can connect
single devices or complete network seg-
ments.
1.1 FRAME SWITCHING FUNCTIONS
Store and Forward
All data received by the RS2-…/… from the
system bus or at the ports are stored and
checked for validity. Invalid and defective
frames (> 1.522 byte or CRC error) as well
as fragments (< 64 byte) are discarded. The
RS2-…/… forwards the valid frames.
Multi address capability
An RS2-…/… learns all source addresses
per port. Only packets with
– unknown addresses
– addresses learnt at this port
– a multi/broadcast address
in the destination address field are sent to
this port.
An RS2-…/… learns up to 4,000 addresses.
This becomes necessary if more than one
terminal device is connected to one or more
ports. In this way several independent sub-
networks can be connected to an RS2-…/….
Learnt addresses
An RS2-…/… monitors the age of the lear-
ned addresses. The RS2-…/… deletes
address entries from the address table
which exceed a certain age (30 seconds).
Note:
Restarting deletes the learned
address entries.
Priority
The RS2-…/… supports two priority queues
(traffic classes complying with IEEE802.1D).
The classification of received data packets
to these classes is done by the priority of
the data packet included in the VLAN tag.
When there is a stong data traffic load this
function prevents data traffic with a higher
priority from disturbance by another data
traffic. The data traffic with the lower priori-
ty is been discarded when the memory or
the transmission chanel is overloaded.
Tagging
(IEEE 802.1Q)
The IEEE 802.1 Q standard designates the
VLAN tag to be included in a MAC data
frame for the VLAN and prioritizing func-
tions. The VLAN tag consists of 2 bytes. It is
inserted between the source address field
and the type field.
For data packets with VLAN tag the RS2-
…/… analyses the 3 bit priority field of the
VLAN tag. The MAC data frame is transmit-
ted unchanged by the RS2-…/….
1.2 SPECIFIC FUNCTIONS OF THE
TP/TX INTERFACE
Link control
The RS2-…/… monitors the connected
TP/TX line segments for short-circuit or
interrupt using regular link test pulses in
accordance with IEEE standard 802.3
10/100BASE-TP/TX. The RS2-…/… does not
transmit any data to a TP/TX segment from
which it does not receive a link test pulse.
Note: A non-occupied interface is assessed
as a line interrupt. The TP/TX line to termi-
nal equipment which is switched off is like-
wise assessed as a line interrupt as the de-
energised bus coupler cannot transmit link
test pulses.
Auto polarity exchange
If the receive line pair is incorrectly connec-
ted (RD+ and RD- switched) polarity is auto-
matically reversed.
Autocrossing
If the autonegotiation function is active, the
RS2-…/… detects the transmit and receive
pairs (MDI, MDI-X). The RS2-…/… auto-
matically configures its port for the correct
transmit and receive pins. Consequently it
does not matter whether you connect
devices using a cross-over or straight cable.
1.3 SPECIFIC FUNCTIONS OF THE
F/O INTERFACE
Link control
According to IEEE 802.3 standard 100BASE-
FX an RS2-…/… monitors the attached F/O
lines for open circuit conditions.
1.4 REDUNDANCY FUNCTIONS
Backbone as a ring (HIPER-Ring)
With the RM function (redundancy mana-
ger) you can close a line structured RS1,
RS2-…/…, MICE or MACH 3000 backbone to
a redundant ring.
If one section fails the ring structure chan-
ges itself back into a line structure within
0.5 seconds in a ring with up to 50 switches.
Redundant coupling of segments
The built-in control intelligence of the RS2-
…/… allows the redundant coupling of
10/100 MBit/s network segments. Within 0.5
seconds an error is detected and the redun-
dant line becomes active.
1.5 GMRP
The GARP Multicast Registration Protocol
(GMRP) describes the distribution of multi-
cast information to other switches. Thus
switches are able to learn multicast addres-
ses. GMRP can be activated by the network
management tool HiVision (from release 5.1
on). State of delivery: GMRP is deactivated
on all ports.
1.6 SECURITY
Port security
An RS2 protects every port from unauthori-
zed access. The following functions are
available for the security monitoring of
every single port:
– Who has access to this port?
– Actions which result on an unauthorized
access
– How to proceed in case of an access of an
unknown user
1.7 FURTHER FUNCTIONS
AND FEATURES
Diagnosis
In case of a reset the RS2-…/… runs a hard-
ware self test. During operation an integra-
ted watch dog (monitoring unit) monitors
the function of the software.
Reset
The RS2-…/… will be reset by the following
actions:
– management
– input voltages fall below a threshold
– watchdog
After a reset the following actions are car-
ried through:
– self test
– initialization
1.8 DISPLAY ELEMENTS
Equipment status
These LEDs provide information about sta-
tuses which affect the function of the entire
RS2-…/….
P1 – Power 1 (green LED)
– lit:
– supply voltage 1 present
– not lit: – supply voltage 1 is less than 18 V
P2 – Power 2
(green LED)
– lit:
– supply voltage 2 present
– not lit: – supply voltage 2 is less than 18 V
FAULT – Failure
(red LED)
– lit:
– The indicator contact is
open, i.e. it indicates an
error.
– not lit:
– The indicator contact is
closed, i.e. it does not
indicate an error.
Stand by –
(green LED)
– lit:
– The standby function is
enabled.
– not lit:
– The standby function is
disabled.
– flashes:
– Memory operation
connected with the
AutoConfiguration
Adapter ACA.
RM – Redundancy Manager
(green/yellow LED)
– lit green:
– RM function active,
redundant port not active
– lit yellow:
– RM function active,
redundant port active
– not lit:
– RM function not active
– flashes:
– Memory operation
connected with the
AutoConfiguration
Adapter ACA.
Port Status
These LEDs display port-related informati-
on.
1 to 7 – Data, Link status
(green/yellow LED)
– not lit:
– no valid link
– lit green:
– valid link
– blinking green (1 single blink per period)
– port is switched to stand-
by (port 1)
– blinking green (3 blinks per period)
– port is disabled
– flashes yellow:– receiving data
– running light: – initialization phase after a
reset
1.9 CONTROLS
2-pin DIP switch (RS2-…/…)
Using the 2-pin DIP switch on the RS2-…/…
front panel
– on RS2-…/… the standby function can be
enabled or disabled with the switch
Stand by
. State of delivery: position 0
(Off), i.e. normal function. In the redun-
dant position the RS2-…/… runs in the
standby mode for redundant coupling of
10/100 MBit/s network segments.
