In a NGN project ,we can't ping SoftX3000's ip address with packets which bigger than 128 bytes ,but with small ping packets ,can be sent perfactly
The network topology :
After checking all the interface use comman disp interface */*/* ,the first two possible reasons were excluded.
But SoftX3000 suppress packets which bigger than 128 bytes to pass , it limited the big packets to pass for securty.
1. The interface negotiation result is different between S3528 and SoftX3000.
2. The Maximum Transmit Unit is too small in some interface .
3. Limited by device .
Some times we should believe our Datacomm device's permence after we try all of the methods, but no use .