The patterns that can be configured to perform BER Test
on an interface.
Bit error measurements are widely used to assess the
performance of a digital transmission equipment. Precise
error measurement requires that the bit pattern transmitted
is known before hand. During BER testing a known pattern is
transmitted on a interface. The pattern received on the
receive side is checked for bit errors. In order to measure
the performance of digital line under real condition
this patterns should also simulate real traffic as closely
as possible. There are two categories of test patterns that
can be generated by a BERT equipment: repetitive and
pseudo-random. The former test patterns are zeroes or ones
or alternating zeroes and ones; the latter patterns are
exponential numbers and conform to CCITT/ITU O.151, O.153.
There are different patterns for different interface speeds.
This object allows the user to configure this BERT patterns.
The supported values are :
Repetitive Patterns
allZeros(1): All Zeroes(Continuous spaces). This is
repeating pattern of zeros(...000...).
The use of this pattern is to test and verify
that the ones density policing mechanism is
functioning properly. This pattern must be
used in circuits optioned for B8ZS.
allOnes(2): All Ones(Continuous Marks). This is repeating
pattern of ones(...1111...). This provides
testing of maximum power level requirements.
The all one pattern test causes the repeater
to consume the maximum amount of power.
If there is insufficient DC span power then the
repeater may begin to fail.
Typically this pattern is used for a simple
continuity check. It may also be used to detect
the presence of unwanted loop in the network.
altOneZero(3): Alternate one/zero pattern(..1010..). This
pattern produces a 50% ones density. It is
used to stress the repeater's DC power
consumption.
doubleAltOnesZeros(4): Double alternate one/zero(..1100..).
oneIn4(5): This pattern is standard loop up remote code.
Typically it is used when the loop up remote test
fails to place the remote system into loopback.
oneIn8(6): This is an eight bit pattern which contains
single one.
This pattern is used primarily to test timing(clock)
recovery and may be used framed or unframed for that
purpose.
This pattern is used to verify frame synchronization
by providing the minimum acceptable pulse density.
oneIn16(7): N repetitive pattern, 1 in 16.
threeIn24(8): This is a 24 bit pattern which contains 3 ones.
The largest string of consecutive zeros is fifteen.
This pattern is used primarily to test timing(clock)
recovery and may be used framed or unframed for that
purpose. This pattern covers both the minimum ones
density and the maximum number of consecutive zeros.
inbandLoopup(9): D4/SF Loopback activate.
Valid only for T1 line.
inbandLoopdown(10): D4/SF Loopback deactivate.
Valid only for T1 line.
Pseudo-Random Patterns
twoE3MinusOne(11): This is 2^3-1 (7 bits in length) pattern.
twoE4MinusOne(12): This is 2^4-1 (15 bits in length) pattern.
twoE5MinusOne(13): This is 2^5-1 (31 bits in length) pattern.
twoE6MinusOne(14): This is 2^6-1 (63 bits in length) pattern.
twoE7MinusOne(15): This is 2^7-1 (127 bits in length) pattern.
twoE7MinusOneFT1Loopup(16): 2^7-1 Fractional
T1 Loop Back Activate.
twoE7MinusOneFT1Loopdown(17): 2^7-1 Fractional
T1 Loop Back Deactivate.
twoE9MinusOne(18): This is 2^9-1(511 bits in length)
pattern specified in ITU O.153.
It has the maximum of 8(non-inverted)
sequential zeros and 9 sequential ones.
twoE10MinusOne(19): This is the 2^10-1(1023 bits in length).
twoE11MinusOne(20): This is the 2^11-1(2047 bits in length)
pattern specified in ITU O.152, O.153.
It has a maximum of 10(non-inverted)
sequential zeros and 11 sequential ones.
This pattern is primarily intended for
error measurements at bit rates of 64kbit/s
and N*64 kbit/s.
twoE15MinusOne(21): This is the 2^15-1(32767 bit length)
pattern as specified in ITU O.151.
It has the maximum of 15(inverted)
sequential zeros.
This sequence is primarily intended for
error and jitter measurements at bit
rates of 1544, 2048, 6312, 8448, 32064 and
44736 kbit/s.
twoE17MinusOne(22): This the 2^17-1(131071 bits in length).
twoE18MinusOne(23): This the 2^18-1(262144 bits in length).
twoE20MinusOne(24): This the 2^20-1(1048575 bits in length)
pattern specified in ITU O.153.It has
the maximum of 19(non-inverted) sequential
zeros. This pattern is primarily intended
for error measurements at bit rates up to
73kbit/s. This pattern stresses the
equalization and timing recovery circuitry
of line repeaters.
twoE20MinusOneQRSS(25): This is the 2^20-1(1048575 bits)
pattern specified in ITU O.151.
This is the pattern with Zero
suppression(Quasi Random Signal Source
This provides the simulation of
live data.
This is primarily intended for
error and jitter measurements
at bit rates of 34368, 139264 kbit/s.
twoE21MinusOne(26): This is the 2^21-1(2097151 bit length).
twoE22MinusOne(27): This is the 2^22-1(4194303 bit length).
twoE23MinusOne(28): This is the 2^23-1(8388607 bit length)
pattern specified in ITU O.151.
Highest stress pseudo-random pattern, with
a maximum of 23 (inverted) sequential zeros
and 23 sequential ones.
This sequence is primarily intended for
error and jitter measurements at bit rates
of 34368 and 139264 kbit/s.
twoE25MinusOne(29): This is the 2^21-1 (33554431 bit length).
twoE28MinusOne(30): This is the 2^28-1 (268435455 bit length).
twoE29MinusOne(31): Highest stress pseudo random pattern,
with a maximum of 29 (inverted) sequential
zeros Specified in ITU 0.150.
twoE31MinusOne(32): It has maximum 31 sequential zeros.
DDS is a special service for transmitting
data in a DS-1 frame.
dds1pattern(33): This sends 100 bytes of all 1s and
then 100 bytes of all 0s to test the stress
clocking of the network.
dds2pattern(34): This sends 100 bytes of a 0x7e pattern
and then 100 bytes of all 0s. This pattern simulates
bit oriented protocol flags for DDS testing.
dds3pattern(35): This pattern sends continuous
bytes of a 0x46 pattern. It is used to simulate
a typical DDS signal.
dds4pattern(36): This pattern sends continuous bytes
of a 0x02 pattern. It is used to stress DDS
clock recovery.
dds5pattern(37): This pattern sends continuous bytes
of a 0x02 pattern.
It is used to stress DDS clock recovery.
userPattern(38): This is any user defined pattern. |
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INTEGER |
allZeros(1), allOnes(2), altOneZero(3), doubleAltOnesZeros(4), oneIn4(5), oneIn8(6), oneIn16(7), threeIn24(8), inbandLoopBackActivate(9), inbandLoopBackDeactivate(10), twoE3MinusOne(11), twoE4MinusOne(12), twoE5MinusOne(13), twoE6MinusOne(14), twoE7MinusOne(15), twoE7MinusOneFT1Loopup(16), twoE7MinusOneFT1Loopdown(17), twoE9MinusOne(18), twoE10MinusOne(19), twoE11MinusOne(20), twoE15MinusOne(21), twoE17MinusOne(22), twoE18MinusOne(23), twoE20MinusOne(24), twoE20MinusOneQRSS(25), twoE21MinusOne(26), twoE22MinusOne(27), twoE23MinusOne(28), twoE25MinusOne(29), twoE28MinusOne(30), twoE29MinusOne(31), twoE31MinusOne(32), dds1pattern(33), dds2pattern(34), dds3pattern(35), dds4pattern(36), dds5pattern(37), userPattern(38) |
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