testing +Jitter+Wander+Data PDH worldwide T-Carrier US and Canada Japan E4 13964 kbps x3 9778 kbps Kbps x3 E3 34368 kbps Kbps T3 44736 kbps 3064 kbps x7 x5 E 8448 kbps Kbps T 631 kbps Kbps x J x3 T1c 315 kbps x J1c 048 kbps T1 1544 kbps J1 x30 Single Channel 64 kbps J4 J3 wwwalbedotelecomcom ALBEDO is a manufacturer of test, measurement and monitoring solutions We supply tools to install, troubleshoot and maintain those infrastructures that support voice, video, internet and data applications ALBEDO core expertise range from SyncE, GbE,, TDM, Jitter/Wander, QoS, and SLA technologies that we have implemented on WAN EMULATORS, Filtering / Aggregation TAPS, handheld TESTERS, and MONITORING Systems Fig 1 PDH and T-carrier hierarchies Fig The frame is the first hierarchy level
Multiplexer A Multiplexer B Errors 64 64 kbps 64 kbps CRC-4 Writer Error Indication Reader Mbps REBE (bit E=1) 64 CRC-4 Reader Error Indication Writer Fig 3 The A multiplexer calculates and writes the CRC code, and the multiplexer B reads and checks the code 64 kbps 64 x30 or x31 E E3 E4 Mbps 8Mbps 8 34 Mbps 34 140 Mbps 8 34 140 Mbps x16 E3 34 Mbps 34 E4 140 Mbps 34 140 E4 Mbps 140 Mbps x64 Fig 4 The PDH hierarchy 140 Standard Binary Rate Size Frame/s Code Amplitude Attenuation G704/73,048 kbps±50 ppm 56 bits 8,000 HDB3 37-300V 6 db G74 8,448 kbps±30 ppm 848 bits 9,96 HDB3 37V 6 db G751 34,368 kbps±0 ppm 1536 bits,3750 HDB3 100V 1 db G751 139,64 kbps±15 ppm 98 bits 47,568 CMI 100V 1 db Table 1 The PDH hierarchy figures
Fig 5 The higher PDH hierarchies A bit-oriented justification process is used to fit tributaries created with clock impairments
8448 kbps (+5 ppm) 8448 kbps (+7 ppm) 8448 kbps (+ ppm) 8448 kbps (-10 ppm) Multiplexer 8 34368 kbps (-10 ppm) 34 1 FAS A S T 1 T T 3 T 4 T 1 T 4 J 1 J J 3 J 4 T 1 T 4 J 1 J J 3 J 4 R 1 R R 4 T 1 T 4 R 3 n R 1 R R 3 R 4 J i 4 justification bits, one per tributary Justification control bit of the i th tributary Fig 6 PDH hierarchies are not synchronous, and variations can be expected in the bit rate clock - in this case a justification mechanism is implemented If all J i =1, then the R i bit does not contain information If all J i =0, then R i contains information Alarm Management: Network Element Multiplexer A Multiplexer B Network Element LOF AIS RAI (bit A=1) AIS Formats: : X : 1 1 n Mbps Mbps CAS 8, 34, 140 Mbps RAI Formats: Time Slot 0 Time Slot 16 Frame 0 C1 0 0 1 1 0 1 1 0 0 0 0 S A S S 1 0 1 A S S S S S a 1 b 1 c 1 d 1 a16 b16 c16 d16 C 0 0 1 1 0 1 1 a b c d a17 b17 c17 d17 3 0 1 A S S S S S a 3 b 3 c 3 d 3 a18 b18 c18 d18 1 FAS A S T 1 T T 3 T 4 T 1 n Fig 7 When a multiplexer detects an LOS or LOF, it sends an RAI to its partner multiplexer and forwards an AIS to the next
ID Detection Criteria AIS LOF LOS RAI FAS error Bit error Code error CRC-LOM CAS-LOM CAS-MRAI CAS-MAIS CRC error Alarm Indication Signal It is detected if there are two or less zeros (ITU-T G775) Loss of Frame alarm It is raised after three consecutive frames with FAS error or three consecutive signalling bits (ITU-T G706) Loss of Frame Signal alarm Remote Alarm Indication It is detected after three consecutive frames with the A bit equal to 1 (ITU-T G73) Frame Alignment Signal error, indicating an incorrect bit in the alignment word Bit sequence mismatch (when the transmitted pattern is known) Violation on coding sequence Cyclic Redundancy Checksum - Loss of Multiframe Activated if there is LOF, and deactivated after one correct FAS and two correct CRC-MFAS (ITU-T G706) Channel-Associated Signalling - Loss of Multiframe Raised after two consecutive MFAS errors or two multiframes with time slot 16 bits equal to 0 (ITU-T G73) Channel-Associated Signalling - Multiframe Remote Alarm Indication Detected after two consecutive frames with the MRAI bit equal to 1 (ITU-T G73) Channel-Associated Signaling - Multiframe Alarm Indication Signal Detected if there are less than three zeros in the time slot 16 during two consecutive multiframes Cyclic Redundancy Check error Raised if one or more bits are erroneous, whenever CRC-LOM is off (ITU-T G706) REBE Remote End Block Error Raised if the first bit of the frames 14 and 16 is 0 (ITU-T G706) Table Mbps events: alarms, errors and event indications ID AIS LOF LOS RAI FAS error Explanation Alarm Indication Signal This is detected if less than six zeros in a frame in the case of 140 Mbps, or less than three zeros in 34 Mbps and 8 Mbps Loss of Frame alarm Raised after four consecutive frames with FAS error Loss of Frame Signal alarm Remote Alarm Indication Detected after two consecutive frames with A equals1 Frame alignment signal error One or more incorrect bits in the alignment word Table 3 PDH events: alarms, errors and event indications for all the hierarchies
DS0 T1 T 64 kbps DS0 1544 Mbps DS1 631 Mbps DS M1 M1 x7 M3 DS1 DS DS3 DS0 T1 64 kbps T1c DS0 1544 Mbps DS1 M1 315 Mbps M11c x DS1 DS1c T3 44736 Mbps DS0 64 kbps T1 DS0 1544 Mbps M1 x8 DS1 DS1 M13 DS3 T3 44736 Mbps Fig 8 T-Carrier hierarchy (US) Fig 9 The T1 frame and superframe
Fig 10 The DS frame or M1 multiplexing and DS3 frame Code e t ype p a at o 00110010 11111111 DS3 equipment failure Service Affecting (SA), requires quick attention 00011110 11111111 DS3 equipment failure Non-Service Affecting (NSA) 00000000 11111111 DS1 equipment failure Service Affecting (SA), requires quick attention 00001010 11111111 DS1 equipment failure Non-Service Affecting (NSA) 00011100 11111111 DS3 LOS Loss of Signal 00101010 11111111 Multiple DS1 LOS Multiple Loss of Signal in the DS1 tributaries 00111100 11111111 Single DS1 LOS Loss of Signal received from a DS1 00000000 11111111 DS3 OOF Out of Frame in the DS3 signal 00101100 11111111 DS AIS Alarm Indication Signal received from a DS Table 4 C-bit parity: alarm and status signal codes
Test and Measurement In-Service-Measurement (ISM) E4 140 140 Ref: 700706 0 0505 Double or simple, frame analyzer Test Equipment Out-of-Service-Measurement (OOSM) E4 140 140 Pattern Generation Error Detection Performance Measurement % ROUTE ALLOCATION OK DEGRADED BAD SERIAL OUTPUT LIMIT OK LIMIT BAD he AT-048 is the ultimate tester designed in 011 & 01 for field engineers that are installing, commissioning and troubleshooting links, Synchonization Networks, and Datacom circuits This instrument, designed and manufactured in Europe by ALBEDO Telecom, is a brand new platform, incorporating the latest available electronics, consequently you will enjoy top performance, high accuracy and, of course, a very competitive price All in one:, nx64, Datacom, Jitter, Wander, Frame Relay Double port Pulse Mask RJ45 balanced interfaces New datacom interfaces with CISCO data cables Display 480 x 7 TFT full color screen xusb and Ethernet ports High performance Extra rugged while lightweight (1kg) VNC remote control Made in EU designed in 01