Packet reassembly processing

1. A method of processing an asynchronous transfer mode (ATM) cell of data into an ATM adaptation layer (AAL) packet, the method comprising:

identifying a first connection identifier (CID) of one or more minipackets in the ATM cell based on a source address and a destination address of the one or more minipackets in the ATM cell;

reassembling the one or more minipackets having the first CID into one or more common part sublayer (CPS) packets;

reassembling the one or more CPS packets having the first CID into a portion of a service specific segmentation and reassembly (SSSAR) conversation;

determining, by a preprocessor, an occurrence of a trigger by:

identifying a second CID of one or more subsequent minipackets based on a source address and a destination address of the one or more subsequent minipackets; and

determining whether the second CID differs from the first CID, and,

if so, generating the trigger;

if not, checking an indication field of the one or more minipackets; and

determining, based on the indication field of a selected minipacket, whether the selected minipacket is a last minipacket having the first CID, and, if so, generating the trigger,

wherein the indication field is a part of an overhead bytes of the selected minipackets;

in response to determining the occurrence of the trigger, sending the portion of the reassembled minipackets having the first CID to a destination processor.

2. The method as recited in claim 1 , wherein determining, by the preprocessor, the occurrence of the trigger further comprises:

checking, by the preprocessor, a timer; and

determining whether the timer expired, and, if so,

generating the trigger.

3. The method of claim 1 , wherein the preprocessor comprises one or more field-programmable gate arrays.

4. The method of claim 1 , wherein the method is implemented as steps executed by a system-on-chip (SoC) network processor.

5. The method of claim 1 , wherein the AAL packet is an AAL type 2 packet.

6. The method of claim 1 , wherein the AAL packet is an AAL type 5 packet.

7. A reassembly system configured to process an asynchronous transfer mode (ATM) cell of data into an ATM adaptation layer (AAL) packet, the system comprising:

one or more preprocessors, each coupled to a multiplexer, each preprocessor configured to:

arrange synchronous transport module data traffic in one or more frames;

identify a first connection identifier (CID) of one or more minipackets in the ATM cell based on a source address and a destination address of the one or more minipackets in the ATM cell;

reassemble the one or more minipackets having the first CID into one or more common part sublayer (CPS) packets;

reassemble the one or more CPS packets having the first CID into a portion of a service specific segmentation and reassembly (SSSAR) conversation;

identify a second CID of one or more subsequent minipackets based on a source address and a destination address of the one or more subsequent minipackets; and

determine whether the second CID differs from the first CID, and,

if so, generating the trigger;

if not, checking an indication field of the one or more minipackets; and

determining, based on the indication field of a selected minipacket, whether the selected minipacket is a last minipacket having the first CID, and, if so, generating the trigger,

wherein the indication field is a part of an overhead bytes of the selected minipackets;

determine all occurrence of the trigger;

in response to determining the occurrence of the trigger, send the portion of the reassembled minipackets having the first CID to a destination processor coupled to the multiplexer.

8. The system of claim 7 , further comprising: a timer, wherein the one or more preprocessors are further configured to:

check the timer; and

determine whether the timer expired, and, if so,

generate the trigger.

9. A non-transitory, machine-readable storage medium, having encoded thereon program code, wherein, when the program code is executed by a machine, the machine implements a method for processing an asynchronous transfer mode (ATM) cell of data into an ATM adaptation layer (AAL) packet, the method comprising:

identifying a first connection identifier (CID) of one or more minipackets in the ATM cell based on a source address and a destination address of the one or more minipackets in the ATM cell;

reassembling the one or more minipackets having the first CID into one or more common part sublayer (CPS) packets;

reassembling the one or more CPS packets having the first CID into a portion of a service specific segmentation and reassembly (SSSAR) conversation;

determining, by a preprocessor, an occurrence of a trigger by:

identifying a second CID of one or more subsequent minipackets based on a source address and a destination address of the one or more subsequent minipackets; and

determining whether the second CID differs from the first CID, and,

if so, generating the trigger;

if not, checking all indication field of the one or more minipackets; and

determining, based on the indication field of a selected minipacket, whether the selected minipacket is a last minipacket having the first CID, and, if so, generating the trigger,

wherein the indication field is a part of an overhead bytes of the selected minipackets;

in response to determining the occurrence of the trigger, sending the portion of the reassembled minipackets having the first CID to a destination processor.

10. The non-transitory, machine-readable storage medium of claim 9 , wherein determining the occurrence of the trigger further comprises:

checking a timer; and

determining whether the timer expired, and, if so,

generating the trigger.

11. The non-transitory, machine-readable storage medium of claim 9 , wherein the AAL packet is an AAL type 2 packet.