編號(hào)

原因

1

Unassiagned number(未分配的號(hào)碼（空號(hào)）)

3

No route to destination(無(wú)至目的地的路由)

6

Channel unacceptable(不可接受的信道)

16

Normal clearing(正常清除)

17

User busy(用戶忙)

18

No user responding(無(wú)用戶響應(yīng))

19

User alerting,no answer(已有用戶提醒，但無(wú)應(yīng)答)

21

Call rejected(呼叫拒絕)

22

Number changed(號(hào)碼改變)

26

Non selected user clearing(清除未選擇的用戶)

27

Destination out of order(終點(diǎn)故障)

28

Incomplete number(無(wú)效號(hào)碼格式（不完全的號(hào)碼）)

29

Facility rejected(設(shè)施被拒絕)

30

Response to status enquiry(對(duì)狀態(tài)詢(xún)問(wèn)的響應(yīng))

31

Normal,unspecified(正常，未規(guī)定)

34

No circuit/channel available(無(wú)電路/信道可用)

38

Network out of order(網(wǎng)絡(luò)故障)