與在其他通信系統(tǒng)中工作原理相同，終端使用IMS進(jìn)行語音通話的第一步就是要先完成注冊；UE通過IMS代理服務(wù)器注冊到CSCF單元；其注冊的方式有兩種：

• 認(rèn)證注冊：REGISTER with Authentication

• 加密認(rèn)證注冊：REGISTER with Authentication and IPSec

1. 認(rèn)證注冊流程（圖）

   2.注冊流程4大步主要內(nèi)容    

    Step 1 : REGISTER --------------------------------

        REGISTER sip:test.3gpp.com SIP/2.0

        f: <sip:+[email]11234567890@test.3gpp.com[/email]>;tag=2722997041

        t: <sip:+[email]11234567890@test.3gpp.com[/email]>

        CSeq: 575513373 REGISTER

        i: 2722997021_2363003016@2001::21f:29ff:fe7c:8f51

        v: SIP/2.0/UDP [2001::21f:29ff:fe7c:8f51]:5060;branch=z9hG4bK656994275

        Max-Forwards: 70

        m: <sip:+11234567890@[2001::21f:29ff:fe7c:8f51]:5060>

        P-Access-Network-Info: 3GPP-E-UTRAN-FDD; utran-cell-id-3gpp=3114800102FFFFFFF

        l: 0

        Authorization:

        Digest uri="sip:test.3gpp.com",

        username="[email]001010123456789@test.3gpp.com[/email]",

        response="",

        realm="test.3gpp.com", 

        nonce=""

        Expires: 7200

         

          首次注冊可能因參數(shù)與認(rèn)證服務(wù)域名不匹配，收到“代碼錯誤”的回復(fù)；








Step 2 : 401 UNAUTHORIZED  --------------------------------

     SIP/2.0 401 Unauthorized

     Via: SIP/2.0/UDP [2001::21f:29ff:fe7c:8f51]:5060;branch=z9hG4bK656994275

     From: <sip:+[email]11234567890@test.3gpp.com[/email]>;tag=2722997041

     To: <sip:+[email]11234567890@test.3gpp.com[/email]>;tag=T3E04A4B5

     Call-ID: 2722997021_2363003016@2001::21f:29ff:fe7c:8f51

     CSeq: 575513373 REGISTER

     Content-Length: 0

     WWW-Authenticate:

     Digest realm="test.3gpp.com",

     nonce="qlWqVapVqlWqVapVqlWqVUUQA5HEt9VVZ3t1TM221cg=",

     qop="auth",

     opaque="MTcyMjU3ODA2NDo=SU1TLVNJUCBTZXJ2ZXI=",

     algorithm=AKAv1-MD5

     P-Associated-URI: <sip:+[email]11234567890@TEST.3GPP.COM[/email]>

     P-Associated-URI: <tel:+11234567890>




                  *STEP2中參數(shù)必須與STEP1中匹配，加密算法需UE支持，否則UE將無法繼續(xù)注冊；

                       參數(shù)nonce是根據(jù)終端的"RAND + AUTN + Server Specific Data"計算所得的認(rèn)證數(shù)據(jù)；




Step 3 : REGISTER -----------------------------------

    REGISTER sip:test.3gpp.com SIP/2.0

    f: <sip:+[email]11234567890@test.3gpp.com[/email]>;tag=2722997284

    t: <sip:+[email]11234567890@test.3gpp.com[/email]>

    CSeq: 575513374 REGISTER

    i: 2722997021_2363003016@2001::21f:29ff:fe7c:8f51

    v: SIP/2.0/UDP [2001::21f:29ff:fe7c:8f51]:5060;branch=z9hG4bK843051065

    Max-Forwards: 70

    m: <sip:+11234567890@[2001::21f:29ff:fe7c:8f51]:5060>

    P-Access-Network-Info: 3GPP-E-UTRAN-FDD; utran-cell-id-3gpp=3114800102FFFFFFF

    l: 0

    Authorization:

    Digest username="[email]001010123456789@test.3gpp.com[/email]",

    realm="test.3gpp.com",

    uri="sip:test.3gpp.com",

    qop=auth,

    nonce="qlWqVapVqlWqVapVqlWqVUUQA5HEt9VVZ3t1TM221cg=",

    nc=00000001,

    cnonce="11259375",

    algorithm=AKAv1-MD5,

    response="a3f549b13f477562f4445b7277cd83c1",

    opaque="MTcyMjU3ODA2NDo=SU1TLVNJUCBTZXJ2ZXI="

    Expires: 7200




             *Expires:為本次注冊有效時間，超時后需要更新







Step 4 : 200 OK -----------------------------------

    SIP/2.0 200 OK

    Via: SIP/2.0/UDP [2001::21f:29ff:fe7c:8f51]:5060;branch=z9hG4bK843051065

    From: <sip:+[email]11234567890@test.3gpp.com[/email]>;tag=2722997284

    To: <sip:+[email]11234567890@test.3gpp.com[/email]>;tag=T44F6AE74

    Call-ID: 2722997021_2363003016@2001::21f:29ff:fe7c:8f51

    CSeq: 575513374 REGISTER

    Contact: <sip:+11234567890@[2001::21f:29ff:fe7c:8f51]:5060>;q=0.500;expires = 7200

    Content-Length: 0

    Date: Mon, 22 Apr 2013 15:43:15 GMT

    Authentication-Info:

    qop=auth,

    rspauth="a3f549b13f477562f4445b7277cd83c1",

    cnonce="11259375",

    nc=00000001

    P-Associated-URI: <sip:+[email]11234567890@TEST.3GPP.COM[/email]>

    P-Associated-URI: <tel:+11234567890>

    P-Associated-URI:  <sip:+[email]11234567890@TEST.3GPP.COM[/email]>

    P-Associated-URI: <tel:+11234567890>

原文來自：http://www.sharetechnote.com/

整理：kangguoying20200924

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