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System Status Trunk Alarms 3
- Thread starter Luqman408
- Start date
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2
- #2
amriddle01
Programmer
The types of alarms:
•Blue alarm— Another message you might receive is that the receiver is getting an Alarm Indication Signal (AIS), which means that a blue alarm indication signal is received. This generally indicates that there is a problem upstream. This is a framed or unframed all-ones signal, in both SF and ESF formats, which is transmitted to maintain transmission continuity. It typically occurs when the far-end channel service unit (CSU) has lost its terminal side equipment. For example, if you shut down your side of the connection, a blue alarm is sent to the remote side.
•Yellow alarm— The receiver has a remote alarm that indicates the presence of a yellow alarm. This means that the downstream CSU is in a LOF or LOS state. It is also a remote site alarm indication (RAI). When the receiver experiences LOS, the transmitter sends a yellow alarm. For SF-formats, a remote alarm is declared when bit 6 on all channels is set to 0 for at least 35 seconds. The alarm is cleared if the same bit is non-zero for 5 seconds or less (usually 1 second). When the format is ESF, a remote alarm indicates if the yellow alarm pattern exists in at least seven out of ten continuous 16-bit intervals. The alarm is cleared if this condition no longer exists for the same time intervals.
•Red alarm— Another typical failure is called a red alarm. A red alarm is usually indicated on the opposite end of the yellow alarm. The red alarm means that the receiver experiences LOS, LOF, or an AIS. A LOS failure is defined in RFC 1406 as "is declared upon observing 175 +/- 75 contiguous pulse positions with no pulses of either positive or negative polarity. The LOS failure is cleared upon observing an average pulse density of at least 12.5% over a period of 175 +/- 75 contiguous pulse positions starting with the receipt of a pulse. For E1 links, the LOS failure is declared when greater than 10 consecutive zeroes are detected." After a red alarm is declared, the device sends a yellow signal to the far end. When the far end receives the yellow signal, it declares a yellow alarm. This message is accompanied by a "receiver has loss of frame" message.
ACS - IP Office Implement
"What the Crocodile Hat....was that?
•Blue alarm— Another message you might receive is that the receiver is getting an Alarm Indication Signal (AIS), which means that a blue alarm indication signal is received. This generally indicates that there is a problem upstream. This is a framed or unframed all-ones signal, in both SF and ESF formats, which is transmitted to maintain transmission continuity. It typically occurs when the far-end channel service unit (CSU) has lost its terminal side equipment. For example, if you shut down your side of the connection, a blue alarm is sent to the remote side.
•Yellow alarm— The receiver has a remote alarm that indicates the presence of a yellow alarm. This means that the downstream CSU is in a LOF or LOS state. It is also a remote site alarm indication (RAI). When the receiver experiences LOS, the transmitter sends a yellow alarm. For SF-formats, a remote alarm is declared when bit 6 on all channels is set to 0 for at least 35 seconds. The alarm is cleared if the same bit is non-zero for 5 seconds or less (usually 1 second). When the format is ESF, a remote alarm indicates if the yellow alarm pattern exists in at least seven out of ten continuous 16-bit intervals. The alarm is cleared if this condition no longer exists for the same time intervals.
•Red alarm— Another typical failure is called a red alarm. A red alarm is usually indicated on the opposite end of the yellow alarm. The red alarm means that the receiver experiences LOS, LOF, or an AIS. A LOS failure is defined in RFC 1406 as "is declared upon observing 175 +/- 75 contiguous pulse positions with no pulses of either positive or negative polarity. The LOS failure is cleared upon observing an average pulse density of at least 12.5% over a period of 175 +/- 75 contiguous pulse positions starting with the receipt of a pulse. For E1 links, the LOS failure is declared when greater than 10 consecutive zeroes are detected." After a red alarm is declared, the device sends a yellow signal to the far end. When the far end receives the yellow signal, it declares a yellow alarm. This message is accompanied by a "receiver has loss of frame" message.
ACS - IP Office Implement
"What the Crocodile Hat....was that?
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1
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amriddle01
Programmer
Or in more plain language:
Red Alarm
Your T1/E1 port will go into red alarm when it cannot maintain synchronization with the remote switch. A red alarm typically indicates either a physical wiring problem, loss of connectivity, or a framing and/or line-coding mismatch with the remote switch.
When your T1/E1 port loses sync, it will transmit a yellow alarm to the remote switch to indicate that it's having a problem receiving signal from the remote switch.
The easy way to remember this is that the R in red stands for "right here" and "receive"... indicating that we're having a problem right here receiving the signal from the remote switch.
Yellow Alarm
(RAI -- Remote Alarm Indication)
Your T1/E1 port will go into yellow alarm when it receives a signal from the remote switch that the port on that remote switch is in red alarm. This essentially means that the remote switch is not able to
maintain sync with you, or is not receiving your transmission.
The easy way to remember this is that the Y in yellow stands for "yonder"... indicating that the remote switch (over yonder) isn't able to see what you're sending.
Blue Alarm
(AIS -- Alarm Indication Signal)
Your T1/E1 port will go into blue alarm when it receives all unframed 1s on all timeslots from the remote switch. This is a special signal to indicate that the remote switch is having problems with its
upstream connection. dahdi_tool and Asterisk don't correctly indicate a blue alarm at this time. The easy way to remember this is that streams are blue, so a blue alarm indicates a problem upstream from
the switch you're connected to.
Hope that helps
ACS - IP Office Implement
"What the Crocodile Hat....was that?
Red Alarm
Your T1/E1 port will go into red alarm when it cannot maintain synchronization with the remote switch. A red alarm typically indicates either a physical wiring problem, loss of connectivity, or a framing and/or line-coding mismatch with the remote switch.
When your T1/E1 port loses sync, it will transmit a yellow alarm to the remote switch to indicate that it's having a problem receiving signal from the remote switch.
The easy way to remember this is that the R in red stands for "right here" and "receive"... indicating that we're having a problem right here receiving the signal from the remote switch.
Yellow Alarm
(RAI -- Remote Alarm Indication)
Your T1/E1 port will go into yellow alarm when it receives a signal from the remote switch that the port on that remote switch is in red alarm. This essentially means that the remote switch is not able to
maintain sync with you, or is not receiving your transmission.
The easy way to remember this is that the Y in yellow stands for "yonder"... indicating that the remote switch (over yonder) isn't able to see what you're sending.
Blue Alarm
(AIS -- Alarm Indication Signal)
Your T1/E1 port will go into blue alarm when it receives all unframed 1s on all timeslots from the remote switch. This is a special signal to indicate that the remote switch is having problems with its
upstream connection. dahdi_tool and Asterisk don't correctly indicate a blue alarm at this time. The easy way to remember this is that streams are blue, so a blue alarm indicates a problem upstream from
the switch you're connected to.
Hope that helps
ACS - IP Office Implement
"What the Crocodile Hat....was that?
all in the help files. no offence but you can't have looked too hard.
See what my brain does when it's not thinking about phones.
See what my brain does when it's not thinking about phones.
amriddle01
Programmer
My answer is far more informative than the help files though Tom
ACS - IP Office Implement
"What the Crocodile Hat....was that?
ACS - IP Office Implement
"What the Crocodile Hat....was that?
the second post was. the first was a cut and paste.
have a star anyway, good advice is good advice.
See what my brain does when it's not thinking about phones.
have a star anyway, good advice is good advice.
See what my brain does when it's not thinking about phones.
- Thread starter
- #7
amriddle01
Programmer
No problem my friend
ACS - IP Office Implement
"What the Crocodile Hat....was that?
ACS - IP Office Implement
"What the Crocodile Hat....was that?
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