Support for DTLSv1.0 protocol
Notes:
DTLSv1.0 protocol is supported on Citrix ADC MPX/SDX (N2 and N3 based), VPX, and MPX 14000 FIPS appliances. It is not supported on external HSMs.
Citrix ADC MPX 14000 FIPS platform is supported in build 12.1–49.x and later.
Support for Intel Coleto based appliances is added in build 12.1-50.x and later. The following appliances ship with Intel Coleto chips:
- MPX 5901/5905/5910
- MPX 8905/8910/8920/8930
- MPX/SDX 26100-100G/26160-100G/26100-200G
- MPX/SDX 15020-50G/15030-50G/15040-50G/15060-50G/15080-50G/15100-50G/15120-50G
- MPX/SDX 15020/15030/15040/15060/15080/15100/15120
The SSL and TLS protocols have traditionally been used to secure streaming traffic. Both of these protocols are based on TCP, which is slow. In addition, TLS cannot handle lost or reordered packets.
UDP is the preferred protocol for audio and video applications, such as Lync, Skype, iTunes, YouTube, training videos, and flash. However, UDP is not secure or reliable. The DTLS protocol is designed to secure data over UDP and is used for applications such as media streaming, VOIP, and online gaming for communication. In DTLS, each handshake message is assigned a specific sequence number within that handshake. When a peer receives a handshake message, it can quickly determine whether that message is the next one expected. If it is, the peer processes the message. If not, the message is queued for handling after all the previous messages have been received.
Create a DTLS virtual server and a service of type UDP. By default, a DTLS profile (nsdtls_default_profile) is bound to the virtual server. Optionally, you can create and bind a user-defined DTLS profile to the virtual server.
Note: RC4 ciphers are not supported on a DTLS virtual server.
DTLS configuration
You can use the command line (CLI) or the configuration utility (GUI) to configure DTLS on your ADC appliance.
Create a DTLS configuration by using the CLI
At the command prompt, type:
add lb vserver <vserver_name> DTLS <IPAddress> <port>
add service <service_name> <IPAddress> UDP 443
bind lb vserver <vserver_name> <udp_service_name>
The following steps are optional:
add dtlsProfile dtls1 -maxretryTime <positive_integer>
set ssl vserver <vserver_name> -dtlsProfileName <dtls_profile_name>
Create a DTLS configuration by using the GUI
- Navigate to Traffic Management > Load Balancing > Virtual Servers.
- Create a virtual server of type DTLS, and bind a UDP service to the virtual server.
- A default DTLS profile is bound to the DTLS virtual server. To bind a different profile, in SSL Parameters, select a different DTLS profile. To create a profile, click the plus (+) next to DTLS Profile.
Support for SNI on a DTLS virtual server
From release 12.1 build 49.x, SNI is supported on a DTLS virtual server. For information about SNI, see Configure an SNI virtual server for secure hosting of multiple sites.
Configure SNI on a DTLS virtual server by using the CLI
At the command prompt, type:
set dtls vserver <vServerName> -SNIEnable ENABLED
bind dtls vserver <vServerName> -certkeyName <string> -SNICert
show dtls vserver <vServerName>
Example:
set ssl vserver v1 -sniEnable ENABLED
bind ssl vserver v1 -certkeyName san2 -sniCert
bind ssl vserver v1 -certkeyName san13 –sniCert
bind ssl vserver v1 -certkeyName san17 –sniCert
sh ssl vserver v1
Advanced SSL configuration for VServer v1:
DH: DISABLED
DH Private-Key Exponent Size Limit: DISABLED
Ephemeral RSA: ENABLED
Refresh Count: 0
Session Reuse: ENABLED
Timeout: 1800 seconds
Cipher Redirect: DISABLED
ClearText Port: 0
Client Auth: DISABLED
SSL Redirect: DISABLED
Non FIPS Ciphers: DISABLED
SNI: ENABLED
OCSP Stapling: DISABLED
HSTS: DISABLED
HSTS IncludeSubDomains: NO
HSTS Max-Age: 0
DTLSv1: ENABLED
Send Close-Notify: YES
Strict Sig-Digest Check: DISABLED
Zero RTT Early Data: DISABLED
DHE Key Exchange With PSK: NO
Tickets Per Authentication Context: 1
DTLS profile name: nsdtls_default_profile
ECC Curve: P_256, P_384, P_224, P_521
1) CertKey Name: ca
CA Certificate OCSPCheck: OptionalCA_Name Sent
2) CertKey Name: san2 Server Certificate for SNI
3) CertKey Name: san17 Server Certificate for SNI
4) CertKey Name: san13 Server Certificate for SNI
1) Cipher Name: DEFAULT
Description: Default cipher list with encryption strength >= 128bit
Done
Configure SNI on a DTLS virtual server by using the GUI
- Navigate to Traffic Management > Load Balancing > Virtual Servers.
- Open a DTLS virtual server and, in Certificates, click Server Certificate.
- Add a certificate or select a certificate from the list and select Server Certificate for SNI.
- In Advanced Settings, click SSL Parameters.
- Select SNI Enable.
Features not supported by a DTLS virtual server
The following options cannot be enabled on a DTLS virtual server:
- SSLv2
- SSLv3
- TLSv1
- TLSv1.1
- TLSv1.2
- Push encrypt trigger
- SSLv2Redirect
- SSLv2URL
- Secure renegotiation
Parameters not used by a DTLS virtual server
A DTLS virtual server ignores the following SSL parameters, even if set:
- Encryption trigger packet count
- PUSH encryption trigger timeout
- SSL quantum size
- Encryption trigger timeout
- Subject/Issuer Name Insertion Format
Configure renegotiation on a DTLS service
From build 49.x, non-secure renegotiation is supported on a DTLS service. You can use the CLI or the GUI to configure this setting.
Configure renegotiation on a DTLS service by using the CLI
At the command prompt, type:
set ssl parameter -denysslreneg NONSECURE
Example:
set ssl parameter -denysslreneg NONSECURE
sh ssl parameter
Advanced SSL Parameters
-----------------------
SSL quantum size : 8 KB
Max CRL memory size : 256 MB
Strict CA checks : NO
Encryption trigger timeout : 100 ms
Send Close-Notify : YES
Encryption trigger packet count : 45
Deny SSL Renegotiation : NONSECURE
Subject/Issuer Name Insertion Format : Unicode
OCSP cache size : 10 MB
Push flag : 0x0 (Auto)
Strict Host Header check for SNI enabled SSL sessions : NO
PUSH encryption trigger timeout : 1 ms
Crypto Device Disable Limit : 0
Global undef action for control policies : CLIENTAUTH
Global undef action for data policies : NOOP
Default profile : DISABLED
SSL Insert Space in Certificate Header : YES
Disable TLS 1.1/1.2 for SSL_BRIDGE secure monitors : NO
Disable TLS 1.1/1.2 for dynamic and VPN services : NO
Software Crypto acceleration CPU Threshold : 0
Hybrid FIPS Mode : DISABLED
Signature and Hash Algorithms supported by TLS1.2 : ALL
SSL Interception Error Learning and Caching : DISABLED
SSL Interception Maximum Error Cache Memory : 0 Bytes
Done
Configure renegotiation on a DTLS service by using the GUI
- Navigate to Traffic Management > Load Balancing > Services.
- Select a DTLS service and click Edit.
- Navigate to SSL > Advanced Settings.
- Select Deny SSL Renegotiation.
Features not supported by a DTLS service
The following options cannot be enabled on a DTLS service:
- SSLv2
- SSLv3
- TLSv1
- TLSv1.1
- TLSv1.2
- Push encrypt trigger
- SSLv2Redirect
- SSLv2URL
- SNI
- Secure renegotiation
Parameters not used by a DTLS service
A DTLS service ignores the following SSL parameters, even if set:
- Encryption trigger packet count
- PUSH encryption trigger timeout
- SSL quantum size
- Encryption trigger timeout
- Subject/Issuer Name Insertion Format
Note:
SSL session reuse handshake fails on a DTLS service because session reuse is not currently supported on DTLS services.
Workaround: Manually disable session reuse on a DTLS service. At the CLI, type:
set ssl service <dtls-service-name> -sessReuse DISABLED
DTLS profile
A DTLS profile with the default settings is automatically bound to a DTLS virtual server. However, you can create a DTLS profile with specific settings to suit your requirement.
Use a DTLS profile with a DTLS virtual server or a VPN DTLS virtual server. You cannot use an SSL profile with a DTLS virtual server.
Create a DTLS profile by using the CLI
add ssl dtlsProfile <name>
show ssl dtlsProfile<name>
Example:
add dtlsProfile dtls1 -helloVerifyRequest ENABLED -maxretryTime 4
Done
show dtlsProfile dtls1
1) Name: dtls1
PMTU Discovery: DISABLED
Max Record Size: 1460 bytes
Max Retry Time: 4 sec
Hello Verify Request: ENABLED
Terminate Session: DISABLED
Max Packet Count: 120 bytes
Done
Create a DTLS profile by using the GUI
Navigate to System > Profiles > DTLS Profiles ** and configure a new profile.
Example for an end-to-end DTLS configuration
enable ns feature SSL LB
add server s1 198.51.100.2
en ns mode usnip
add service svc_dtls s1 DTLS 443
add lb vserver v1 DTLS 10.102.59.244 443
bind ssl vserver v1 -ciphername ALL
add ssl certkey servercert -cert servercert_aia_valid.pem -key serverkey_aia.pem
bind ssl vserver v1 -certkeyname servercert
bind lb vserver lb1 svc_dtls
sh lb vserver v1
v1 (10.102.59.244:4433) - DTLS Type: ADDRESS
State: UP
Last state change was at Fri Apr 27 07:00:27 2018
Time since last state change: 0 days, 00:00:04.810
Effective State: UP
Client Idle Timeout: 120 sec
Down state flush: ENABLED
Disable Primary Vserver On Down : DISABLED
Appflow logging: ENABLED
No. of Bound Services : 1 (Total) 0 (Active)
Configured Method: LEASTCONNECTION
Current Method: Round Robin, Reason: A new service is bound BackupMethod: ROUNDROBIN
Mode: IP
Persistence: NONE
L2Conn: OFF
Skip Persistency: None
Listen Policy: NONE
IcmpResponse: PASSIVE
RHIstate: PASSIVE
New Service Startup Request Rate: 0 PER_SECOND, Increment Interval: 0
Mac mode Retain Vlan: DISABLED
DBS_LB: DISABLED
Process Local: DISABLED
Traffic Domain: 0
TROFS Persistence honored: ENABLED
Retain Connections on Cluster: NO
1) svc_dtls (10.102.59.190: 4433) - DTLS State: UP Weight: 1
Done
sh ssl vserver v1
Advanced SSL configuration for VServer v1:
DH: DISABLED
DH Private-Key Exponent Size Limit: DISABLED Ephemeral RSA: ENABLED Refresh Count: 0
Session Reuse: ENABLED Timeout: 1800 seconds
Cipher Redirect: DISABLED
ClearText Port: 0
Client Auth: DISABLED
SSL Redirect: DISABLED
Non FIPS Ciphers: DISABLED
SNI: DISABLED
OCSP Stapling: DISABLED
HSTS: DISABLED
HSTS IncludeSubDomains: NO
HSTS Max-Age: 0
DTLSv1: ENABLED
Send Close-Notify: YES
Strict Sig-Digest Check: DISABLED
Zero RTT Early Data: DISABLED
DHE Key Exchange With PSK: NO
Tickets Per Authentication Context: 1
DTLS profile name: nsdtls_default_profile
ECC Curve: P_256, P_384, P_224, P_521
1) CertKey Name: servercert Server Certificate
1) Cipher Name: DEFAULT
Description: Default cipher list with encryption strength >= 128bit
2) Cipher Name: ALL
Description: All ciphers supported by NetScaler, excluding NULL ciphers
Done
sh service svc_dtls
svc_dtls (10.102.59.190:4433) - DTLS
State: UP
Last state change was at Fri Apr 27 07:00:26 2018
Time since last state change: 0 days, 00:00:22.790
Server Name: s1
Server ID : None Monitor Threshold : 0
Max Conn: 0 Max Req: 0 Max Bandwidth: 0 kbits
Use Source IP: NO
Client Keepalive(CKA): NO
Access Down Service: NO
TCP Buffering(TCPB): NO
HTTP Compression(CMP): NO
Idle timeout: Client: 120 sec Server: 120 sec
Client IP: DISABLED
Cacheable: NO
SC: OFF
SP: OFF
Down state flush: ENABLED
Monitor Connection Close : NONE
Appflow logging: ENABLED
Process Local: DISABLED
Traffic Domain: 0
1) Monitor Name: ping-default
State: UP Weight: 1 Passive: 0
Probes: 5 Failed [Total: 0 Current: 0]
Last response: Success - ICMP echo reply received.
Response Time: 2.77 millisec
Done
sh ssl service svc_dtls
Advanced SSL configuration for Back-end SSL Service svc_dtls:
DH: DISABLED
DH Private-Key Exponent Size Limit: DISABLED Ephemeral RSA: DISABLED
Session Reuse: ENABLED Timeout: 1800 seconds
Cipher Redirect: DISABLED
ClearText Port: 0
Server Auth: DISABLED
SSL Redirect: DISABLED
Non FIPS Ciphers: DISABLED
SNI: DISABLED
OCSP Stapling: DISABLED
DTLSv1: ENABLED
Send Close-Notify: YES
Strict Sig-Digest Check: DISABLED
Zero RTT Early Data: ???
DHE Key Exchange With PSK: ???
Tickets Per Authentication Context: ???
DTLS profile name: nsdtls_default_profile
ECC Curve: P_256, P_384, P_224, P_521
1) Cipher Name: DEFAULT_BACKEND
Description: Default cipher list for Backend SSL session
Done
sh dtlsProfile nsdtls_default_profile
1) Name: nsdtls_default_profile
PMTU Discovery: DISABLED
Max Record Size: 1459 bytes
Max Retry Time: 3 sec
Hello Verify Request: DISABLED
Terminate Session: DISABLED
Max Packet Count: 120 bytes
Done
DTLS cipher support
Note:
From release 12.1 build 49.x, ADH ciphers are no longer supported with the DTLS protocol.
How to read the tables:
Unless a build number is specified, a cipher suite is supported for all builds in a release.
Example:
- 10.5, 11.0, 11.1, 12.0, 12.1: All builds of 10.5, 11.0, 11.1, 12.0, 12.1 releases.
- NA: not applicable.
DTLS cipher support on Citrix ADC VPX, MPX/SDX (N2 and N3 based) appliances
| Cipher Suite Name | Hex Code | Wireshark Cipher Suite Name | Builds Supported (front end) | Builds Supported (back end) |
|---|---|---|---|---|
| TLS1-AES-256-CBC-SHA | 0x0035 | TLS_RSA_WITH_AES_256_CBC_SHA | 11.0, 11.1, 12.0, 12.1 | 12.0, 12.1 |
| TLS1-AES-128-CBC-SHA | 0x002f | TLS_RSA_WITH_AES_128_CBC_SHA | 11.0, 11.1, 12.0, 12.1 | 12.0, 12.1 |
| SSL3-DES-CBC-SHA | 0x0009 | TLS_RSA_WITH_DES_CBC_SHA | 11.0, 11.1, 12.0, 12.1 | An |
| SSL3-DES-CBC3-SHA | 0x000a | TLS_RSA_WITH_3DES_EDE_CBC_SHA | 11.0, 11.1, 12.0, 12.1 | 12.0, 12.1 |
| SSL3-EDH-RSA-DES-CBC3-SHA | 0x0016 | TLS_DHE_RSA_WITH_3DES_EDE_CBC_S | 11.0, 11.1, 12.0, 12.1 | NA |
| SSL3-EDH-RSA-DES-CBC-SHA | 0x0015 | TLS_DHE_RSA_WITH_DES_CBC_SHA | 11.0, 11.1, 12.0, 12.1 | NA |
| TLS1-ECDHE-RSA-AES256-SHA | 0xc014 | TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA | 12.1 | 12.1 |
| TLS1-ECDHE-RSA-AES128-SHA | 0xc013 | TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA | 12.1 | 12.1 |
| TLS1-ECDHE-RSA-DES-CBC3-SHA | 0xc012 | TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA | 12.1 | NA |
| TLS1-DHE-RSA-AES-128-CBC-SHA | 0x0033 | TLS_DHE_RSA_WITH_AES_128_CBC_SHA | 12.1 | 12.1 |
| TLS1-DHE-RSA-AES-256-CBC-SHA | 0x0039 | TLS_DHE_RSA_WITH_AES_256_CBC_SHA | 12.1 | 12.1 |
DTLS cipher support on the Citrix ADC MPX 14000 FIPS platform
Note: Enlightened Data Support (EDT) is supported on the FIPS platform in build 49.x and later if the following conditions are met:
- UDT MSS value set on StoreFront is 900.
- Windows client version is 4.12 or later.
- DTLS enabled VDA version is 7.17 or later.
- Non-DTLS VDA version is 7.15 LTSR CU3 or later.
| Cipher suite Name | Hex Code | Wireshark Cipher suite Name | Builds Supported (front end) | Builds Supported (back end) |
|---|---|---|---|---|
| TLS1-AES-256-CBC-SHA | 0x0035 | TLS_RSA_WITH_AES_256_CBC_SHA | 11.0, 11.1, 12.0, 12.1–49.x | 12.0, 12.1–49.x |
| TLS1-AES-128-CBC-SHA | 0x002f | TLS_RSA_WITH_AES_128_CBC_SHA | 11.0, 11.1, 12.0, 12.1–49.x | 12.0, 12.1–49.x |
| SSL3-DES-CBC-SHA | 0x0009 | TLS_RSA_WITH_DES_CBC_SHA | 11.0, 11.1, 12.0, 12.1–49.x | NA |
| SSL3-DES-CBC3-SHA | 0x000a | TLS_RSA_WITH_3DES_EDE_CBC_SHA | 11.0, 11.1, 12.0, 12.1–49.x | 12.0, 12.1–49.x |
| SSL3-EDH-RSA-DES-CBC3-SHA | 0x0016 | TLS_DHE_RSA_WITH_3DES_EDE_CBC_S | 11.0, 11.1, 12.0, 12.1–49.x | NA |
| SSL3-EDH-RSA-DES-CBC-SHA | 0x0015 | TLS_DHE_RSA_WITH_DES_CBC_SHA | 11.0, 11.1, 12.0, 12.1–49.x | NA |
| TLS1-ECDHE-RSA-AES256-SHA | 0xc014 | TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA | 12.1–49.x | 12.1–49.x |
| TLS1-ECDHE-RSA-AES128-SHA | 0xc013 | TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA | 12.1–49.x | 12.1–49.x |
| TLS1-ECDHE-RSA-DES-CBC3-SHA | 0xc012 | TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA | 12.1–49.x | NA |
| TLS1-DHE-RSA-AES-128-CBC-SHA | 0x0033 | TLS_DHE_RSA_WITH_AES_128_CBC_SHA | 12.1–49.x | 12.1–49.x |
| TLS1-DHE-RSA-AES-256-CBC-SHA | 0x0039 | TLS_DHE_RSA_WITH_AES_256_CBC_SHA | 12.1–49.x | 12.1–49.x |
In this article
- DTLS configuration
- Support for SNI on a DTLS virtual server
- Features not supported by a DTLS virtual server
- Parameters not used by a DTLS virtual server
- Configure renegotiation on a DTLS service
- Features not supported by a DTLS service
- Parameters not used by a DTLS service
- DTLS profile
- Example for an end-to-end DTLS configuration
- DTLS cipher support
- DTLS cipher support on Citrix ADC VPX, MPX/SDX (N2 and N3 based) appliances
- DTLS cipher support on the Citrix ADC MPX 14000 FIPS platform