310TH SPACE WING (AFRC) (310 SW) - Schriever Air Force Base

GENERAL INFORMATION
15. DSN POLICIES AND INSTRUCTIONS
a. General: DSN is the principle long-haul, voice communications
network within the Defense Communications System, providing
unsecured direct distance dialing service worldwide through a
system of government-owned and leased automatic switching
facilities. The purpose of DSN is to handle essential command and
control, operations, intelligence, logistic and administrative traffic.
b. Local Capability: Subscribers at Schriever AFB have the
capability of direct dialing outgoing calls, by dialing “94” and the
seven-digit number.
c. Pre-emption: Automatic pre-emption capability for high
precedence calls exists on DSN lines. When a circuit is preempted
automatically for a higher precedence call, the circuit user receives
a high frequency tone lasting less than three seconds. Upon
receiving the pre-emption tone, hang up immediately and reestablish
your call later. In order to assure prompt completion and
to avoid pre-emption by another call once conversation is
established, calls with precedence of Priority or above should be
placed with the DSN operator, but only in cases where they are
mission essential and must be placed immediately.
d. Overseas Calls: All Overseas DSN calls must be placed with the
base operator.
Contact your unit TCO or alternate for a control number, give it to
the operator, along with the precedence of the call and desired
number. Stay on the line until the operator completes the call.
e. USE OF THE DEFENSE SWITCHED NETWORK (DSN):
1. Will be authorized for only official communications.
2. Will be restricted to:
a) Only calls essential and require a timeliness that cannot be
obtained by other means, and would stand the scrutiny afforded a
commercial toll call.
b) The minimum time required to accomplish the official
business and will not normally exceed five minutes.
c) The use of precedence level in accordance with the subject
matter of the call as established in the Joint Uniform Telephone
Communications Precedence System.
d) The use of graphic facsimile or unsecured voice-data devices
only when approved by the Chief of the Military Services and heads
of DoD agencies or activities. Voice-data, facsimile and graphic
service in DSN normally will not exceed a continuous transmission
time of 15 minutes or a total transmission time of one hour during
normal business hours.
3. Will not be authorized for:
a) Use directly or indirectly by any non-appropriated fund
activities (clubs, exchanges, and other unofficial activities) provided
telephone service at post, camp, station or base level except when
approved by the Joint Chief of Staff.
b) Calls within an installation, metropolitan area or those
confined geographical areas where other existing governmentprovided
local telephone service is adequate.
c) Unofficial or personal calls.
d) Off-net extension of call into the commercial system at a
distant switchboard, except where such extension has been
previously approved by the local authorities controlling the
switchboard.
f. TELEPHONE MONITORING: The users of the DSN system should
be aware that the DoD system is for official use only and is subject
to management monitoring in accordance with DoD directive
4640.6, subject “Telephone Monitoring.”
g. DSN USER CALLING INSTRUCTIONS:
1. Routine DSN calls:
(a) Users with dial-access to DSN should:
(1) Verify the DSN number.
(2) Listen for dial tone.
(3) Dial DSN ACCESS CODE. (94)
(4) Dial the seven-digit DSN number.
(b) Users needing operator assistance for DSN should:
(1) Verify the DSN number.
(2) Dial the operator and give precedence of the call and
number desired - stay on the line until the operator completes call
2. Precedence and Inter-Area DSN calls:
To place precedence or inter-area DSN calls all users should:
(a) Verify the DSN number.
(b) Dial the operator and give the following information: The
precedence of the call and the DSN number desired.
h. DSN USER ASSISTANCE AND PRECEDENCE CALLS: Your local
base operator provides call assistance and conferencing for DSN
users. Your local operator also provides DSN directory assistance.
Dial “O” when encountering difficulty in dialing a routine
precedence call or if higher than routine precedence is required.
i. PRECEDENCE SYSTEM: The National Communications System
(NCS) Voice Precedence System, which was established by NCS
Memorandum 1-70, dated 14 February 1970, is for use by all
authorized users of DoD voice communications facilities. Since the
effectiveness of the system depends on the cooperation of the
people authorized to use it, users must: (1) be familiar with the
purposes of each precedence category and the type of call that is
assigned the precedence and (2) exercise care not to request or
use a precedence higher than required.
1. FLASH
a) Preempts any calls of lower precedence.
b) Precedence is reserved for alerts, warnings or other
emergency actions having immediate bearing on national,
command or area security.
Do Not Discuss Classified Information on the Telephone 7
general information