Albalá Ingenieros IPA2000C01 User manual

IPA2000C01
DVB-ASI AND DVB-IP AUTOMATIC CHANGE-OVER SWITCH WITH TS
FAILURE DETECTION FUNCTIONS AND SEAMLESS SWITCHING
Version 1.0
Albalá Ingenieros, S.A.
Medea, 4 - 28037 Madrid - Spain
10 January 2017 - © Albalá Ingenieros S.A. - All rights reserved

IPA2000C01

IPA2000C01
DVB-ASI AND DVB-IP AUTOMATIC CHANGE-OVER SWITCH WITH TS FAILURE
DETECTION FUNCTIONS AND SEAMLESS SWITCHING
Version 1.0
1. DESCRIPTION ...................................................................................................................... 5
1.1. The IPA2000C01 ............................................................................................................................. 5
1.2. Features ............................................................................................................................................. 7
1.3. Block diagram .................................................................................................................................. 8
2. SPECIFICATIONS ................................................................................................................. 9
3. INSTALLATION .................................................................................................................. 11
3.1. Initial inspection .......................................................................................................................... 11
3.2. Safety instructions ...................................................................................................................... 11
3.3. Environmental considerations ................................................................................................ 12
3.4. Installing the module in the mounting frame ................................................................... 12
3.5. Interconnection ............................................................................................................................ 13
3.5.1. Ethernet connections ........................................................................................................ 13
3.5.2. Electrical DVB-ASI video connections .......................................................................... 13
4. OPERATION ...................................................................................................................... 15
4.1. Front panel description .............................................................................................................. 15
4.2. Functional description ............................................................................................................... 15
4.2.1. Operation in automatic mode ........................................................................................ 16
4.2.2. Operation in semi-automatic mode ............................................................................. 16
4.2.3. Operation in manual mode ............................................................................................. 16
4.3. Description of the TS over IP encapsulators/de-encapsulators ................................... 16
4.4. System latencies .......................................................................................................................... 17
4.5. Module remote control and supervision ............................................................................. 20
4.5.1. Details of the IPA2000C01 registers ............................................................................. 21
5. GLOSSARY ........................................................................................................................ 31
6. REGULATIONS .................................................................................................................. 33
7. VERSIONS ......................................................................................................................... 35

IPA2000C01

Albalá Ingenieros | Manual IPA2000C01
1. DESCRIPTION
1.1. The IPA2000C01
The IPA2000C01 module is an automated switch for DVB-ASI and DVB-over-IP signals
that operates according to the presence of signals at the inputs, reception of a sync
stream and the status of the inputs with regards to errors present as per ETSI TR 101 290
V1.2.1 as a first priority, based upon the priority criteria set by the user for each of the
inputs.
The unit provides two DVB-ASI inputs/outputs labeled ASI 1 and ASI 2 and two 1 Gbps
Ethernet interfaces over which it can receive an additional two DVB-over-IP streams DVB
(UDP and RTP with and without FEC) labeled IP RX 1 and IP RX2 as well as transmit two
DVB-over-IP streams (IP TX 1 and IP TX 2). Furthermore, if an EOP2000C01 module is
installed in the slot immediately to the left of the IPA2000C01 then two auxiliary ASI
inputs become available, and if an EOP2000C02 is installed immediately to the right,
then two auxiliary ASI outputs become available.
The IPA2000C01 provides two analysis channels that can be assigned to any of its six
inputs. At any given time the two signals being analyzed are directed to two different
destinations that can be the ASI outputs or the IP outputs.
Depending upon the type of stream being received, the IPA2000C01 module can operate
in two different modes. One is for use with any DVB Transport Stream and the other can
only be used with DVB-T type Transport Streams. The characteristics of each of these
modes are described in the following:
• Generic DVB mode:
- Allows both seamless and non-seamless operation.
-Error detection can activate for any of the parameters indicated in ETSI TR 101 290
V1.2.1 as a First Priority, which are the following:
- TS_sync_loss. Loss of synchronization.
- Sync_byte_error. Sync_byte not equal 0x47.
- PAT_error. Errors that prevent the PAT from being obtained.
- Continuity_count_error. Errors in the packet continuity counter.
- PMT error. Errors that prevent the PMT from being obtained.
- PID_error. Referred PID does not occur for a user specified period.
- The 1 PPS reference input via the backplane is not used.
5

Albalá Ingenieros | Manual IPA2000C01
• Dedicated DVB-T mode:
- Seamless-only operation.
-Error detection occurs according to all the parameters indicated in NO DVB-T mode
and according to the presence of a megaframe sync (MIP packets).
-The 1 PPS reference input is used to measure the delay with which the input signals
arrive and to set the delay of the output signal.
-The output delay is fixed and is programmed independently from the delay of the
input signals since it must be greater than the input signal delay in order for the unit
to operate properly.
In order to perform seamless switching of the DVB-T streams coming into the
IPA2000C01, the module provides a 13.5MHz reference input and a 1 PPS reference
input that come over the backplane from another module installed in the same
mounting frame. This allows the various Transport Streams to be synchronized.
In addition to functioning as an automatic switch, the IPA2000C01 can be used for other
functions such as conversion of DVB-ASI transport streams to DVB over IP and vice versa,
elimination of jitter in the transport streams being transmitted over IP and the
conversion of IP protocols such as elimination or insertion of forward error correction
(FEC), conversion from UTP to RTP, etc.
The IPA2000C01 provides three switching modes: selection of the input can be
Automatic, Semiautomatic or Manual. Any change in the selection of the input or the
status of the inputs is flagged in the control software.
It is possible to monitor the IPA2000C01 status remotely using a TLE2001C02
communications controller module installed in the same mounting frame. In addition,
certain controller modules provide SNMP management and the ability to record events
in a file including date and time information for further analysis.
The IPA2000C01 is a TL2000 terminal line module and can be housed in a two rack unit
(2 RU) UR2000 mounting frame.
6

Albalá Ingenieros | Manual IPA2000C01
1.2. Features
•Automatic change-over switch for DVB Transport Stream signals with seamless
switching capabilities.
•Allows error detection for two channels and selection of one channel for routing to the
output at any given time based upon the switching mode, the error status and the
priority assigned to each channel.
• The signal being analyzed by each channel can come from six possible input interfaces:
- Two DVB-ASI signal connectors located on the front panel of the module.
-Two DVB-ASI buses on the backplane of the mounting frame coming from an
auxiliary module located in the slot immediately to the left of the IPA2000C01.
-Two DVB-over-IP receivers (UDP and RTP with and without FEC) connected to two
gigabit Ethernet interfaces.
•The unit provides six output interfaces to which any selected channel can be routed.
These are:
- Two DVB-ASI signal connectors located on the front panel of the module.
-Two DVB-ASI buses on the backplane of the mounting frame coming from an
auxiliary module located in the slot immediately to the right of the IPA2000C01.
-Two DVB-over-IP transmitters (UDP and RTP with and without FEC) connected to two
gigabit Ethernet interfaces.
•The error criteria for the input channels that can be selected are defined in the First
Priority table of ETSI TR 101 290 V1.2.1 together with the presence of a megaframe sync
signal in DVB-T mode.
• Provides three modes of operation: Automatic, Semiautomatic and Manual.
• The priority of the input channels can be set by the user.
• The DVB-ASI inputs include automatic equalizers.
• Error indicator LEDs for each of the input channels are provided on the front panel.
•Module control and supervision can be done remotely when the mounting frame is
equipped with a TLE2001C02 communications controller module.
• Low power.
7

Albalá Ingenieros | Manual IPA2000C01
1.3. Block diagram
8

Albalá Ingenieros | Manual IPA2000C01
2. SPECIFICATIONS
DVB-ASI signal input
Connector BNC
Impedance 75Ω ± 1 %
Return loss >17dB up to 270 MHz
Number of inputs 2
Equalizable cable length:
Belden 8281 >300 m
Belden 1694A >350 m
DVB-ASI signal output
Connector BNC
Impedance 75Ω ± 1 %
Return loss >17dB up to 270 MHz
Number of outputs 2
Amplitude 800mVpp ± 10 %
Rise and fall time (20 % - 80 %) 640 ps typ.
DVB-ASI signal
Signal format According to EN 50083-9 standard
DVB-IP signal
Supported protocols According to {$SMPTE_ST_2022_1} and
{$SMPTE_ST_2022_2} standards
Ethernet interface
Connector RJ45
Encoding and electrical characteristics:
1000BASE-T According to IEEE std 802.3ab standard
100BASE-T According to IEEE std 802.3u standard
10BASE-T According to IEEE std 802.3i standard
Operating modes Auto-Negotiation speed,
full duplex/half duplex
Supported protocols IP, ARP, ICMP, UDP, RTP,
IGPM (v2 y v3), VLAN
General
Power consumption 6.5 W
Operating temperature range 0 .. 50 °C
Approximate weight 213 g
9

Albalá Ingenieros | Manual IPA2000C01
IPA2000C01
10

Albalá Ingenieros | Manual IPA2000C01
3. INSTALLATION
THE IPA2000C01 MODULE CONTAINS ELECTRONIC DEVICES SENSITIVE TO
ELECTROSTATIC DISCHARGE. Always use antistatic bags clearly identified
with a high degree of shielding for storage and transportation.
3.1. Initial inspection
Verify that the package has been properly handled during transport. After opening the
packaging, check that the IPA2000C01 module is inside.
You must notify your Albalá Ingenieros distributor or dealer of any damage or defects
observed.
Follow the instructions in this manual to install this module in the mounting frame.
3.2. Safety instructions
•This equipment must be connected to a mains outlet with a protective
earth connection. Never use extension cords that do not have protective
earthing connection. The lack of an effective electrical connection between
the ground pin in the mains input connector of the equipment and the
protective earth of the electrical power distribution can cause serious harm.
•All modules of the Albalá Ingenieros TL2000 terminal line can be
hot-plugged or unplugged without suffering any damage or affecting the
processes that are currently taking place in other modules in the same
mounting frame.
•The IPA2000C01 module and the mounting frame should always be
installed, maintained, operated and removed by personnel with sufficient
technical qualifications. The equipment should never be placed in damp
areas, near splashing liquid, or in explosive or corrosive atmospheres.
Neither modules nor mounting frames can be used in applications that
could endanger human life.
11

Albalá Ingenieros | Manual IPA2000C01
3.3. Environmental considerations
This symbol indicates that this equipment must be deposited at a collection
point for proper waste treatment once it has reached the end of its useful
life.
3.4. Installing the module in the mounting frame
The following steps should be followed in order to install a IPA2000C01 module in the
mounting frame.
1 - Remove the blank panel covering the front of the empty slot chosen for installing the
IPA2000C01 in the mounting frame.
2 - Insert the IPA2000C01 module into the front of the mounting frame. The edges of the
card slide into two plastic guides inside the mounting frame.
3 - Secure the module to the mounting frame using the two front screws.
After these steps, the module is ready to be connected to other equipment.
12

Albalá Ingenieros | Manual IPA2000C01
3.5. Interconnection
The arrangement of the front panel connectors of the IPA2000C01 module is shown in
the following figure.
Front panel of the IPA2000C01
The IPA2000C01 module provides DVB-ASI Transport Stream input and outputs as well
as Ethernet interfaces.
There are four connectors for the various interface types, described in the following:
-ASI 1 and ASI 2 are BNC input/output connectors for DVB-ASI signals.
-ETHERNET 1 and ETHERNET 2 are Ethernet interfaces used to receive up to two
Transport Streams over IP, IP RX 1 and IP RX 2 and also to transmit two output
Transport Streams over IP, IP TX 1 and IP TX 2.
Furthermore, the module can operate together with other auxiliary modules located in
the slots to its left or right to provide an additional two DVB-ASI inputs or outputs,
respectively.
The front panel has not been designed to support mechanical stress. All cabling in the
rack where the mounting frame is located should be properly supported so that the front
panel does not provide mechanical support.
3.5.1. Ethernet connections
The Ethernet ports uses RJ-45 connectors. The cable used should be UTP Cat 5 or
better (Cate 5e or Cat 6) in order to guarantee proper 1Gbit/s operation.
13

Albalá Ingenieros | Manual IPA2000C01
3.5.2. Electrical DVB-ASI video connections
All DVB-ASI digital video electrical connections are BNC type. Below are several
recommendations to consider when wiring electrical signals.
BNC connectors used on cables must be suitable for the high frequencies of DVB-ASI
digital video signals: it is strongly recommended to use high quality connectors from
well known manufacturers.
All coaxial cable used must be Belden 8281 or similar. This type provides the greatest
lengths because it is used to calculate the equalizers in the IPA2000C01. Cables
carrying signal between the module and the devices should use single piece
construction, avoiding spliced sections with double BNC female or barrel connectors.
If it is necessary to split the cable into two sections the same type of wire should be
used in both sections.
The use of analog video coaxial cables (RG-59 type or similar) is not recommended for
digital video except for very short distances.
14

Albalá Ingenieros | Manual IPA2000C01
4. OPERATION
This section describes the significance of the front panel indicators of the IPA2000C01
module and their remote control and monitoring ability.
4.1. Front panel description
The appearance of the front panel and the elements it contains are shown in the
following illustration.
Front panel of the IPA2000C01
In addition to the connectors previously described in the Interconnection section the
front panel includes the following indicators and controls:
CH.1,
CH.2: These LEDs light up in red (FAIL) to indicate that their corresponding input
channel does not have a valid signal. These LEDs blink if a valid signal is present
but the delay in that signal exceeds the programmed DVB-T output delay (only in
DVB-T mode).
These LEDs light up in green (OK) when their corresponding input have a valid
signal.
These LEDs light up in blue (S.OK) to indicate that both processing channels have a
valid signal and that seamless switching between them is possible.
15

Albalá Ingenieros | Manual IPA2000C01
4.2. Functional description
4.2.1. Operation in automatic mode
In this operating mode the IPA2000C01 automatically selects the highest priority
input that does not contain errors.
The error detection can be configured to activate due to: absence of signal at the
input, reception of an incorrect stream sync or megaframe sync (megaframe sync only
in DVB-T mode) or for any of the other error conditions defined as First Priority as per
ETSI TR 101 290 V1.2.1.
In order to avoid unnecessary switching, the recovery time after an error condition has
been cleared can be programmed. By default this value is two seconds. Also, when an
error is detected at the selected input, the IPA2000C01 only switches to a different
input if that input is error-free.
The recovery time in NO DVB-T mode must be greater than two seconds since the
time required two synchronize the two streams is greater than in DVB-T mode. The
programmed recovery time should be set higher when the size of the buffer used (the
number of packets) is greater and when the bitrate of the streams being aligned is
lower.
4.2.2. Operation in semi-automatic mode
This operating mode minimizes the number of switching events. The IPA2000C01 will
only switch if the selected input develops an error and the other input is error-free.
4.2.3. Operation in manual mode
Manual mode is useful for maintenance of the installation. The user selects the input
to be used and no switching will occur even if an error occurs in that input.
Selection of Manual Mode can only be done via the control software.
4.3. Description of the TS over IP encapsulators/de-encapsulators
Several different protocols exist for encapsulation of DVB transport streams over IP.
•Protocol UDP: This is the simpler protocol that can be used, but it is the least robust.
UDP consists of grouping up to seven TS packets and transmitting them within one
UDP packet. This protocol does not detect dropped packets nor packets arriving out of
sequence.
•Protocol RTP: This protocol is similar to UDP with respect to the way in which packets
16

Albalá Ingenieros | Manual IPA2000C01
are grouped for transmission but adds a header that includes a continuity flag for
detection of dropped packets and packets received out of sequence along with a
timestamp to facilitate elimination of jitter introduced by the network. When using the
RTP protocol a single frame (FEC Type A) or two frames (FEC Type B) of auxiliary data
can be sent in order to correct errors or dropped packets. When using the RTP protocol
the IPA2000C01 can be configured to substitute dropped and non-recoverable packets
of the TS with null packets.
4.4. System latencies
When transporting DVB frames over ASI interfaces the latency introduced due to
serialization and de-serialization is minimal in comparison to other delays that may exist
in the system. During encapsulation of the DVB over IP frames mechanisms are
employed to correct errors and absorb any jitter generated by the IP networks. These
mechanisms introduce delays in the transport of the frames that may on occasion need
to be accounted for. This section describes the latencies introduced for each of the
modules within the IPA2000C01:
•IP Transmitters:
The latency introduced by the IP transmitter is negligible in comparison with the other
latencies and can be assumed to be equal to the number TS packets transmitted in each
IP packet. If error correction is employed during transmission then the delay for each FEC
packet is configurable as per the SMPTE 2022-1-2007 standard.
•IP Receivers:
The latency of the IP receiver depends upon the transmission protocol used and
dynamically adapts based upon the protocol detected at the input.
- UDP: The latency equals 12 IP packets.
-RTP without FEC: The latency equals 12 IP packets (in order to permit reordering of up
to ten packets as per the standard).
-RTP with FEC: The latency depends upon the size of the correction matrix used and is
calculated as follows: Latency = (2 x L x D) + 10. This latency stems from the column
FEC packets which can be transmitted with a delay of up to 2 x L x D IP packets (as per
the standard) and ten reordering margin packets.
•Output buffer:
The IPA2000C01 includes a buffer at the output whose operation depends on the
operation mode of the module:
-DVB-T Mode: In this mode the user sets the network delay, equal to the delay that
the output TS must have with respect to the 1 PPS reference signal received by the
IPA2000C01, and the buffer absorbs the difference between the input and the
output. In order to guarantee seamless switching between inputs the TS output
delay must be 50ms greater than the TS input delays received. This difference is due
17

Albalá Ingenieros | Manual IPA2000C01
to the response time of the frame synchronization error detectors.
When the IPA2000C01 operates in this mode the delay fields in the "General" tab of
the control software display the delay of the transport streams received with respect
to the 1 PPS reference signal. The delay is measured at the input of the output buffer
after IP de-encapsulation.
-Non-seamless DVB-T Mode: This operating mode is appropriate for work with signals
that suffer from high levels of jitter. In this case the buffer is used to absorb the jitter
introduced by the IP network and the error correction mechanisms. The output
latency depends upon the selected size of the buffer, which ranges from 32 to 32767
TS packets. The latency decreases as the bitrate increases and also decreases as the
size of the buffer decreases, however the smaller the buffer the lower the amount of
jitter that can be absorbed.
The PLL used to generate the output packet frequency of the IPA2000C01 can be
configured to operate with two different bandwidths: one wide and one narrow. The
wide bandwidth is best for transport streams with variable bitrates because it allows
the bitrate to vary without overflowing the buffer. The narrow bandwidth is best for
transport streams with a fixed bitrate because it allows extremely low jitter in the
DVB output frame.
The two most important components of the IP frame jitter consist of the jitter
introduced by the network itself due to the packet routing mechanisms and the jitter
introduced by the IP receiver when recovering dropped packets. This second source of
jitter depends upon the error correction scheme being used. The worst case is a burst
of 20 dropped and recovered IP packets within a transmission of seven TS packets per
IP packet (RTP with FEC and L = 20) which represents 140 TS packets. In order to
absorb the jitter created in such a case a buffer of at least 256 packets is necessary.
When the IPA2000C01 operates in this mode the delay fields in the "General" tab of
the control software display the latency of each input. The latency introduced by this
buffer affects both the DVB-ASI outputs and the DVB over IP outputs.
-Seamless non-DVB-T Mode: This operating mode is appropriate for switching
between identical signals with stable bitrates and low jitter. In this case the buffer is
used to compensate for the delay between the two inputs and achieve seamless
switching. When operating in this mode a small buffer size and a narrow bandwidth
filter are recommended in order to minimize the jitter introduced in the output
signal during switching.
An additional reason that a small buffer size is recommended when the IPA2000C01
operates in this mode is that buffer size affects the recovery time before seamless
switching can be performed. The larger the buffer size the longer the seamless
switching recovery time.
In order to perform seamless switching the buffer size must always be greater than
the difference in the delay between the signals being switched - otherwise these
delays cannot be compensated for. The recommended buffer size is equal to twice
the difference in delay between the two signals. Since buffer size is specified in ASI
packets whereas the delay is normally measured in milliseconds the bitrate of the
18

Albalá Ingenieros | Manual IPA2000C01
two signals being switched must be known in order to calculate the proper buffer
size. Several example are listed as follows.
The difference in delay between two signals is 100ms and their bitrate is
20Mbit/s. The minimum buffer size for proper delay compensation between the
signals measured in number of packets is (0.1 s x 20.000.000 bit/s) / (188
bytes/packet x 8 bits/byte) = 1329 packets. The recommended buffer size is twice
this size, or 2659 packets.
The difference in delay between two signals is 100ms and their bitrate is
20Mbit/s. Furthermore, one of the signals suffers from jitter of up to 100ms. In
this case the difference in delay between the two signals can be as high as
200ms. Following the recommendation for a buffer size of twice the maximum
delay yields 2 x (0.2 s x 20.000.000 bit/s) / (188 bytes/packet x 8 bits/byte) = 5319
packets.
If the difference in delay between the two signals is unknown, the information
provided by the IPA2000C01's control software can be used to determine this value.
In order to find the difference in delay the buffer must be set to a sufficiently large
value and then the delay indicators for the two signals at the inputs should be read
while the seamless switching indicators are active to calculate the difference
between them. Then, the steps outlined in the previous examples can be followed in
order to adjust the buffer size. If the input signals are not the same or the buffer is
not large enough to properly perform delay compensation, the delays for the selected
inputs will not settle and the seamless switching indicators will not activate.
When using this operating mode another parameter that is highly important to
configure to ensure that seamless switching can be performed is the recovery time.
This is the time period that must elapse from the moment that the error status of a
given input clears until switching occurs (automatic mode) or becomes possible
(semi-automatic mode). In non-DVB-T seamless mode the synchronization time
between inputs depends upon the buffer size and the bitrate of the signals, therefore
the recovery time must be set high enough so that the module can realign the
frames. The maximum time that the module requires in order to realign the transport
streams is twice the size of the buffer. For example:
The difference in delay between two signals is 100ms, their bitrate is 20Mbit/s
and the buffer size has been set to 3000 packets. The minimum recovery time
necessary to assure seamless switching is 2 x (3000 packets x 188 bytes/packet x
8bits/byte) / 20.000.000 bit/s = 0.45 seconds.
The minimum buffer time to ensure seamless switching should be at least 50ms, as
this is the time required to detect a loss of signal by the frame synchronization error
detectors.
19

Albalá Ingenieros | Manual IPA2000C01
HUB/SWITCH
TL2000
COMMUNICATIONS
CONTROLLER MODULE
OTHER TL2000
MODULES
Ethernet
Ethernet
Ethernet
Ethernet
REMOTE CONTROL UNIT
TLE2001 PSU2000 PSU2000
TLE2001 PSU2000 PSU2000
UR2000 INTERNAL BUS
UR2000 INTERNAL BUS
Module remote control and supervision
4.5. Module remote control and supervision
The IPA2000C01 requires remote control for configuration.
In order to perform remote configuration and supervision of the module an optional
TLE2001C02 model remote communications controller must be installed in the
mounting frame.
The main function of the communications control module is to interface between a
10/100 Ethernet port and the internal bus of the mounting frame. The following
illustration shows the most common control situations: from a computer or control
panel via Ethernet.
Certain communications control modules provide additional, more advanced functions
such as an SNMP agent, logging of status changes of the modules and a Web interface
for remote control, etc.
Software for simple configuration and supervision with a GUI for multiple modules can
be downloaded from the Albalá Ingenieros website.
20