Xerox WorkCentre 3550 Technical manual

Xerox WorkCentre 3550
Information Assurance Disclosure Paper
Version 1.2
Prepare by:
Mark Bixler
Xerox Corporation
800 Phillips Roa
Webster
, New York 14
580

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©2011 Xerox Corporation. All rights reserve . Xerox an the sphere of connectivity esign are tra emarks of
Xerox Corporation in the Unite States an /or other counties.
Other company tra emarks are also acknowle ge .
Document Version: 1.3 (March 2011).

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1. INTRODUCTION ..................................................................................................................................5
1.1. Purpose .................................................................................................................................................................................... 5
1.2. Target Audience ................................................................................................................................................................... 5
1.3. Disclai er ............................................................................................................................................................................... 5
2. DEVICE DESCRIPTION .......................................................................................................................6
2.1. Security-relevant Subsyste s ......................................................................................................................................... 7
2.1.1. Physical Partitioning .......................................................................................................................................................................7
2.1.2. Security Functions allocate to Subsystems ........................................................................................................................8
2.2. Controller ................................................................................................................................................................................ 9
2.2.1. Purpose ................................................................................................................................................................................................9
2.2.2. Memory Components ....................................................................................................................................................................9
2.2.3. External Connections .................................................................................................................................................................. 10
2.2.4. USB Ports ......................................................................................................................................................................................... 10
2.3 Fax Module .......................................................................................................................................................................... 11
2.3.1. Purpose ............................................................................................................................................................................................. 11
2.3.2. Har ware ......................................................................................................................................................................................... 11
2.4. Scanner ................................................................................................................................................................................. 11
2.4.1. Purpose ............................................................................................................................................................................................. 11
2.4.2. Har ware ......................................................................................................................................................................................... 11
2.5. Local User Interface (LUI) ............................................................................................................................................. 12
2.5.1. Purpose ............................................................................................................................................................................................. 12
2.5.2. Har ware ......................................................................................................................................................................................... 12
2.6. Marking Engine (also known as the I age Output Ter inal or IOT) .......................................................... 12
2.6.1. Purpose ............................................................................................................................................................................................. 12
2.6.2. Har ware ......................................................................................................................................................................................... 12
2.6.3. Control an Data Interfaces .................................................................................................................................................... 12
2.7. Syste Software Structure ........................................................................................................................................... 13
2.7.1. Open-source components ......................................................................................................................................................... 13
2.7.2. OS Layer in the Controller ......................................................................................................................................................... 13
2.7.3. Network Protocols ........................................................................................................................................................................ 14
2.8. Logical Access ..................................................................................................................................................................... 15
2.8.1. Network Protocols ........................................................................................................................................................................ 15
2.8.2. Ports ................................................................................................................................................................................................... 16
2.8.3. IP Filtering ....................................................................................................................................................................................... 20
3. SYSTEM ACCESS ................................................................................................................................ 21
3.1. Authentication Model ..................................................................................................................................................... 21

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3.2. Login and Authentication Methods ........................................................................................................................... 21
3.2.1. System A ministrator Login [All pro uct configurations] ........................................................................................... 21
3.2.2. User authentication ..................................................................................................................................................................... 21
3.3. Syste Accounts ............................................................................................................................................................... 24
3.3.1. Printing [Multifunction mo els only] .................................................................................................................................... 24
3.3.2. Network Scanning [Multifunction mo els only] .............................................................................................................. 24
3.4. Diagnostics .......................................................................................................................................................................... 24
4. SECURITY ASPECTS OF SELECTED FEATURES ...................................................................... 25
4.1. SMart eSolutions ............................................................................................................................................................... 25
4.2.1 Meter Assistant .............................................................................................................................................................................. 25
4.2.2 Supplies Assistant ......................................................................................................................................................................... 25
4.2.3 Summary .......................................................................................................................................................................................... 25
5. RESPONSES TO KNOWN VULNERABILITIES ......................................................................... 26
5.1. Security @ Xerox (www.xerox.co /security) .......................................................................................................... 26
6. APPENDICES ....................................................................................................................................... 27
6.1. Appendix A – Abbreviations ......................................................................................................................................... 27
6.2. Appendix B – Supported MIB Objects ....................................................................................................................... 29
6.3. Appendix C –Standards .................................................................................................................................................. 31
6.4. Appendix E – References ................................................................................................................................................ 32

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1. Intro uction
The WorkCentre 3550 multifunction systems are among the latest versions of Xerox copier an multifunction
evices for the general office.
1.1. Purpose
The purpose of this ocument is to isclose information for the WorkCentre pro ucts with respect to evice security.
Device Security, for this paper, is efine as how image ata is store an transmitte , how the pro uct behaves in a
networke environment, an how the pro uct may be accesse , both locally an remotely. Please note that the
customer is responsible for the security of their network an the WorkCentre pro ucts o not establish security for
any network environment.
The purpose of this ocument is to inform Xerox customers of the esign, functions, an features of the WorkCentre
pro ucts relative to Information Assurance (IA).
This ocument oes NOT provi e tutorial level information about security, connectivity, PDLs, or WorkCentre
pro ucts features an functions. This information is rea ily available elsewhere. We assume that the rea er has a
working knowle ge of these types of topics. However, a number of references are inclu e in the Appen ix.
1.2. Target Au ience
The target au ience for this ocument is Xerox fiel personnel an customers concerne with IT security.
1.3. Disclaimer
The information in this ocument is accurate to the best knowle ge of the authors, an is provi e without warranty
of any kin . In no event shall Xerox Corporation be liable for any amages whatsoever resulting from user's use or
isregar of the information provi e in this ocument inclu ing irect, in irect, inci ental, consequential, loss of
business profits or special amages, even if Xerox Corporation has been a vise of the possibility of such amages.

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2. Device Description
This pro uct consists of an input ocument han ler an scanner, marking engine inclu ing paper path, controller,
an user interface.
Figure 2-1 WorkCentre Multifunction Syste
Document Fee er & Scanner (IIT)
Marking Engine (IOT)
Paper Trays
User Interface (UI)
The Network Controller is
located on the left rear side of
the machine in WorkCentre
3550 products.
Output Bin
USB Host Port

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2.1. Security-relevant Subsystems
2.1.1. Physical Partitioning
The security-relevant subsystems of the pro uct are partitione as shown in Figure 2-2.
Figure 2-2 Syste functional block diagra

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2.1.2. Security Functions allocate to Subsystems
Security Function Subsyste
System Authentication
Controller
Graphical User Interface
Network Authentication
Controller
Graphical User Interface
Cryptographic Operations
Controller
User Data Protection – SSL
Controller
User Data Protection – IP Filtering
Controller
User Data Protection – IPSec
Controller
Network Management Security
Controller
Fax Flow Security
Fax Mo ule
Controller
Graphical User Interface
Security Management
Controller
Graphical User Interface
Table 1 Security Functions allocated to Subsyste s

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2.2. Controller
2.2.1. Purpose
The controller provi es both network an irect-connect external interfaces, an enables copy, print, email, network
scan an LanFAX functionality. Network scanning an LanFAX are stan ar features. The controller also
incorporates a proprietary web server that exports a Web User Interface (WebUI) through which users can submit
jobs an check job an machine status, an through which system a ministrators can remotely a minister the
machine.
The controller contains the image path, which uses proprietary har ware an algorithms to process the scanne
images into high-quality repro uctions. Scanne images may be temporarily buffere in DRAM to enable electronic
pre-collation, sometimes referre to as scan-once/print-many. When pro ucing multiple copies of a ocument, the
scanne image is processe an buffere in the DRAM in a proprietary format. The buffere bitmaps are then rea
from DRAM an sent to the Image Output Terminal (IOT) for marking on har copy output. For long ocuments, the
pro uction of har copy may begin before the entire original is scanne , achieving a level of concurrency between the
scan an mark operations.
The controller operating system is pSOS v2.5. The controller works with the User Interface (UI) assembly to provi e
system configuration functions. A System A ministrator PIN must be entere at the UI in or er to access these
functions.
2.2.2. Memory Components
Volatile Me ory
Type (SRAM, DRAM,
etc)
Size
User
Modifiable
(Y/N)
Function or U
se
Process to Sanitize
SDRAM 256/512
MB
Expan able
to 512 MB
Main Memory Remove power
Additional Infor ation:
Non-Volatile Me ory
Type (
Flash, EEPROM,
etc)
Size
User
Modifiable
(Y/N)
Function or Use
Process to Sanitize
Flash 32 MB No Operating System, PDL
Interpreters, Fonts, MIB, Fax
Journal List, Fax Dialing, Co e
use for sche uling the
marking of jobs
None
Flash ROM 1 MB No Backup None
Flash 8 MB No Fax/Font Backup None
Additional Infor ation: All memory liste above contains co e for execution an configuration information. No user or job
ata is permanently store in this location.
Table 2 Controller e ory co ponents

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2.2.3. External Connections
Table 3 Controller External Connections
Figure 2-3 Back panel connections
2.2.4. USB Ports
The WorkCentre 3550 contains a host connector for a USB flash rive, enabling printing from USB, scanning to USB
an uploa of software upgra e files.
Autorun is isable on this port. No executable files will be accepte by the port.
Mo ifying the software upgra e or save machine settings files will make the files unusable on a WorkCentre 3550.
The machine settings that can be save an restore by a service technician are limite to controller parameters that
are nee e for normal operation.
Both ports can be isable by an A min via the WebUI.
USB
USB port and location Purpose
USB 2.0 Host port Printing from USB, scanning to USB, uploa of software upgra e files
USB 2.0 Target port Direct-connect printing
Table 4 USB Ports
Interface Description / Usage
1 Foreign Device Interface (FDI) Allows connection of optional access
control har ware
2 PEK (Pro uct Enablement Key)
Rea er Slot
Use for initial pro uct configuration.
3 USB 2.0 Target Port Direct-connect printing
4 Ethernet 10/100/1000 Network connectivity
5 FAX line 1, RJ-11 Supports FAX Mo em T.30 protocol
only
6 Extension Telephone Socket
(EXT), RJ11
Allows connection of telephone
7 USB 2.0 Host Port (Not Picture
– see Figure 2-1)
Printing from USB, scanning to USB,
uploa of software upgra e files

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2.3 Fax Mo ule
2.3.1. Purpose
The embe e FAX service uses the installe embe e fax car to sen an receive images over the telephone
interface.
2.3.2. Har ware
The fax car connects irectly to the Main Controller processor car . The fax car oes not have its own processor an local
memory but uses the Main processor an reserve Flash memory. The car contains a fax-only mo em that supports the
T.30 protocol. If anything other than the T.30 protocol is etecte , the mo em will isconnect. Internal logical interfaces
maintain separation between Fax an network.
Volatile Me ory Description
Type (SRAM, DRAM, etc)
Size
Use
r Modifiable
(Y/N)
Function or Use
Process to Clear:
None n/a n/a n/a n/a
Additional Infor ation:
Non-Volatile Me ory Description
Type (Flash, EEPROM, etc)
Size
User Modifiable
(Y/N)
Function or Use
Process to Clear:
Flash 7MB N FAX Backup None
Addi
tional Infor ation:
Table 5 Fax Module e ory co ponents
2.4. Scanner
2.4.1. Purpose
The purpose of the scanner is to provi e mechanical transport of har copy originals an to convert har copy
originals to electronic ata.
2.4.2. Har ware
The scanner converts the image from har copy to electronic ata. An optional ocument han ler moves originals
into a position to be scanne . The scanner provi es enough image processing for signal con itioning an
formatting. The scanner oes not store scanne images. All other image processing functions are in the main
controller.

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2.5. Local User Interface (LUI)
2.5.1. Purpose
The LUI etects har button actuations, an provi es text an graphical prompts to the user. Images are not
transmitte to or store in the LUI. The Start har button is locate on the LUI panel.
2.5.2. Har ware
Volatile Me ory Description
Type (SRAM, DRAM, etc)
Size
User Modifiable
(Y/N)
Function or Use
Process to Clear:
RAM 2KB N User Interface volatile memory; no
user image ata store
Power Off System
Additional Infor ation:
All memory liste above contains co e for execution an configuration information. No user or job ata is permanently store in this location.
Non-Volatile Me ory Description
Type (Flash, EEPROM, etc)
Size
User Modifiable
(Y/N)
Function or Use
Process to Clear:
PROM 64KB N No user image ata store None
Additional Infor ation:
All memory liste above contains co e for execution an configuration information. No user or job ata is store in this location.
Table 6 User Interface e ory co ponents
2.6. Marking Engine (also known as the Image
Output Terminal or IOT)
2.6.1. Purpose
The Marking Engine performs copy/print paper fee ing an transport, image marking an fusing, an ocument
finishing. Images are not store at any point in these subsystems.
2.6.2. Har ware
The marking engine is comprise of paper supply trays an fee ers, paper transport, laser scanner, xerographics, an
paper output. The marking engine contains a CPU, BIOS, RAM an Non-Volatile Memory.
2.6.3. Control an Data Interfaces
Images an control signals are transmitte from the main controller to the marking engine across a proprietary
interface.

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2.7. System Software Structure
2.7.1. Open-source components
Open-source components in the connectivity layer implement high-level protocol services. The security-relevant
connectivity layer components are:
•Apache 2.2.11, with mo _ssl integrate
(http an https)
•Apache Xerces2 Java
•Open1x
•OpenSLP
•NetBSD Project
•libupnp
•UUID library
•wpa_supplicant
•l ns
•Info-zip
•TWAIN sample Data Source an
Application
•WTL v8.0
•CUPS library
•libjpeg v6b
•libxml2
•Expat XML Parser
•Unico e
•Kerberos 5
•sorttable
•Little CMS v1.15
•libst c++
•CUPS relate stuff
•part of linux kernel
•Spi erMonkey Engine
•OpenSSL v0.9.8e
•Open LDAP v2.1.17
•libpng
•zlib v2.4
•libtiff
•tinyxml
2.7.2. OS Layer in the Controller
The OS layer inclu es the operating system, network an physical I/O rivers. The controller operating system is
pSOS v2.5.
The crypto library for IPSec is provi e by the OpenSSL Toolkit..
IP Filtering is also provi e as a loa able kernel mo ule.

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2.7.3. Network Protocols
Figure 2- is an interface iagram epicting the protocol stacks supporte by the evice, annotate accor ing to the
DARPA mo el.
Figure 2-4 IPv4 Network Protocol Stack

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Figure 2-5 IPv6 Network Protocol Stack
2.8. Logical Access
2.8.1. Network Protocols
The supporte network protocols are liste in Appen ix C an are implemente to in ustry stan ar specifications
(i.e. they are compliant to the appropriate RFC) an are well-behave protocols. There are no ‘Xerox unique’
a itions to these protocols.
2.8.1.1. IPSec
The evice supports IPSec tunnel mo e. The print channel can be secure by establishing an IPSec association
between a client an the evice. A share secret is use to encrypt the traffic flowing through this tunnel. SSL must
be enable in or er to set up the share secret.
When an IPSec tunnel is establishe between a client an the machine, the tunnel will also be active for
a ministration with SNMPv2 tools (HP Open View, etc.), provi ing security for SNMP SETs an GETS with an
otherwise insecure protocol. SNMP Traps may not be secure if either the client or the evice has just been reboote .
IP Filtering can be useful to prevent SNMP calls from non-IPSec clients.
Once an IPSec channel is establishe between two points, it stays open until one en reboots or goes into power
saver,. Only network clients an servers will have the ability to establish an IPSec tunnel with the machine. Thus

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evice-initiate operations (like scanning) cannot assume the existence of the tunnel unless a print job (or other
client initiate action) has been previously run since the last boot at either en of the connection.
2.8.2. Ports
The following table summarizes all potential open ports an subsequent sections iscuss each port in more etail.
Default
Port #
Type Service name
25 TCP SMTP
53 UDP DNS
68 UDP BOOTP/DHCP
80 TCP HTTP
88 UDP/TCP Kerberos
137 UDP NETBIOS- Name Service
138 UDP NETBIOS-Datagram Service; SMB filing an Scan template retrieval
139 TCP NETBIOS; SMB filing an Scan template retrieval
161 UDP SNMP
162 UDP SNMP trap
389 UDP LDAP
396 TCP Netware
427 TCP/UDP SLP
443 TCP SSL
515 TCP LPR
546 UDP DHCPv6
631 TCP IPP
636 TCP sLDAP
1124 TCP/UDP Network Scan Utility
1900 UDP SSDP
3003 TCP HTTP/SNMP reply
5200 TCP UPnP
5353 UDP Multicast DNS
6000 UDP SetIP Utility
7000 UDP LTP Utility
9100 TCP Raw IP
9400 TCP TWAIN for Network Utility
9401 TCP TWAIN for Network Utility
Table 76 Network Ports
Please note that there is no FTP port in this list. FTP is only use to export scanne images an to retrieve Scan Job
Templates, an will open port 21 on the remote evice. An FTP port is never open on the controller itself.
2.8.2.1. Port 25, SMTP
This uni irectional port is open only when Scan to E-mail or Internet Fax (I-Fax) is exporting images to an SMTP
server, or when email alerts are being transmitte . SMTP messages & images are transmitte to the SMTP server
from the evice.
2.8.2.2. Port 53, DNS
Designating a DNS server will allow the evice to resolve omain names. This can be configure via the Local UI or
WebUI.

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2.8.2.3. Port 68, DHCP
This port is use only when performing DHCP, an is not open all of the time. To permanently close this port, DHCP
must be explicitly isable . This is one in User Tools via the Local User Interface or via the TCP/IP page in the
Properties tab on the WebUI.
2.8.2.4. Port 80, HTTP
The embe e web pages communicate to the machine through a set of unique APIs an o not have irect access
to machine information:
Figure 2-6 HTTP
The HTTP port can only access the HTTP server resi ing in the controller. The embe e HTTP server is Apache. The
purpose of the HTTP server is to:
•Give users information of the status of the evice;
•View the job queue within the evice an elete jobs;
•Allow users to ownloa print rea y files an program Scan to File Job Templates;
•Allow remote a ministration of the evice. Many settings that are on the Local UI are replicate in the
evice’s web pages. Users may view the properties of the evice but not change them without logging into the
machine with a ministrator privileges.
The HTTP server can only host the web pages resi ent on the evice. It oes not an cannot act as a proxy server to
get outsi e of the network the evice resi es on. Hence the server cannot access any networks (or web servers)
outsi e of the customer firewall.
When the evice is configure with an IP a ress, it is as secure as any evice insi e the firewall. The web pages are
accessible only to authorize users of the network insi e the firewall.
This service (an port) may be isable in User Tools via the Local User Interface or via the TCP/IP page in the
Properties tab on the Web UI. Please note that when this is isable , IPP Port 631 is also isable .
HTTP may be secure by enabling Secure Sockets Layer.
2.8.2.4.1. Proxy Server
The evice can be configure to communicate through a proxy server. Features that can make use of a proxy server
inclu e the Automatic Meter Rea feature, scanning to a remote repository, or retrieving scan templates from a
remote template pool.
Network
Network Controller
http
server
I
n
t
e
r
n
a
l
A
P
I
machine
information
request
response
request
response

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2.8.2.5. Port 88, Kerberos
This port is only open when the evice is communicating with the Kerberos server to authenticate a user, an is only
use only to authenticate users in conjunction with the Network Scanning feature. To isable this port,
authentication must be isable , an this is accomplishe via the Local User Interface.
This version of software has Kerberos 5.1.1 with DES (Data Encryption Stan ar ) an 64-bit encryption. The Kerberos
co e is limite to user authentication, an is use to authenticate a user with a given Kerberos server as a vali user
on the network. Please note that the Kerberos server (a 3r party evice) nee s to be set up for each user. Once the
user is authenticate , the Kerberos software has complete its task. This co e will not an cannot be use to encrypt
or ecrypt ocuments or other information.
This feature is base on the Kerberos program from the Massachusetts Institute of Technology (MIT). The Kerberos
network authentication protocol is publicly available on the Internet as freeware at
http://web.mit.e u/kerberos/www/. Xerox has etermine that there are no export restrictions on this version of the
software. However, there are a few eviations our version of Kerberos takes from the stan ar Kerberos
implementation from MIT. These eviations are:
1) The evice oes not keep a user’s initial authentication an key after the user has been authenticate . In a
stan ar Kerberos implementation, once a user is authenticate , the evice hol s onto the authentication for a
programme timeout (the usual efault is 12 hours) or until the user removes it (prior to the timeout perio ). In
the Xerox implementation, all traces of authentication of the user are remove once they have been
authenticate to the evice. The user can sen any number of jobs until the user logs off the system, either
manually or through system timeout.
2) The evice ignores clock skew errors. In a stan ar implementation of Kerberos, authentication tests will fail if a
evice clock is 5 minutes (or more) ifferent from the Kerberos server. The reason for this is that given enough
time, someone coul reverse engineer the authentication an gain access to the network. With the 5-minute
timeout, the person has just 5 minutes to reverse engineer the authentication an the key before it becomes
invali . It was etermine uring the implementation of Kerberos for our evice that it woul be too ifficult for
the user/SA to keep the evice clock in sync with the Kerberos server, so the Xerox instantiation of Kerberos has
the clock skew check remove . The isa vantage is that this gives malicious users unlimite time to reverse
engineer the user’s key. However, since this key is only vali to access the Network Scanning features on a
evice, possession of this key is of little use for nefarious purposes.
3) The evice ignores much of the information provi e by Kerberos for authenticating. For the most part, the
evice only pays attention to information that in icates whether authentication has passe . Other information
that the server may return (e.g. what services the user is authenticate for) is ignore or isable in the Xerox
implementation. This is not an issue since the only service a user is being authenticate for is access to an e-
mail irectory. No other network services are accessible from the Local UI.
Xerox has receive an opinion from its legal counsel that the evice software, inclu ing the implementation of a
Kerberos encryption protocol in its network authentication feature, is not subject to encryption restrictions base on
Export A ministration Regulations of the Unite States Bureau of Export A ministration (BXA). This means that it
can be exporte from the Unite States to most estinations an purchasers without the nee for previous approval
from or notification to BXA. At the time of the opinion, restricte estinations an entities inclu e terrorist-
supporting states (Cuba, Iran, Libya, North Korea, Su an an Syria), their nationals, an other sanctione entities
such as persons liste on the Denie Parties List. Xerox provi es this information for the convenience of its customers
an not as legal a vice. Customers are encourage to consult with legal counsel to assure their own compliance with
applicable export laws.
2.8.2.6. Ports 137, 138, 139, NETBIOS
For print jobs, these ports support the submission of files for printing as well as support Network Authentication
through SMB. Port 137 is the stan ar NetBIOS Name Service port, which is use primarily for WINS. Port 138
supports the CIFS browsing protocol. Port 139 is the stan ar NetBIOS Session port, which is use for printing. Ports
137, 138 an 139 may be configure in the Properties tab of the evice’s web page.
For Network Scanning features, ports 138 an 139 are use for both outboun (i.e. exporting scanne images an
associate ata) an inboun functionality (i.e. retrieving Scan Templates). In both instances, these ports are only
open when the files are being store to the server or templates are being retrieve from the Template Pool. For these
features, SMB protocol is use .

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2.8.2.7. Ports 161, 162, SNMP
These ports support the SNMPv1, SNMPv2c, an SNMPv3 protocols. Please note that SNMP v1 oes not have any
passwor or community string control. SNMPv2 relies on a community string to keep unwante people from
changing values or browsing parts of the MIB. This community string is transmitte on the network in clear text so
anyone sniffing the network can see the passwor . Xerox strongly recommen s that the customer change the
community string upon pro uct installation. SNMP is configurable, an may be explicitly enable or isable in the
Properties tab of the evice’s web pages.
SNMP traffic may be secure if an IPSec tunnel has been establishe between the agent (the evice) an the
manager (i.e. the user’s PC).
The evice supports SNMPv3, which is an encrypte version of the SNMP protocol that uses a share secret. Secure
Sockets Layer must be enable before configuring the share secret nee e for SNMPv3.
2.8.2.8. Port 389, LDAP
This is the stan ar LDAP port use for a ress book queries in the Scan to Email feature.
2.8.2.9. Port 396, Netware
This configurable port is use when Novell Netware is enable to run over IP.
2.8.2.10. Port 427, SLP
When activate , this port is use for service iscovery an a vertisement. The evice will a vertise itself as a printer
an also listen for SLP queries using this port. It is not configurable. This port is explicitly enable / isable in the
Properties tab of the evice’s web pages.
2.8.2.11. Port 443, SSL
This is the efault port for Secure Sockets Layer communication. This port can be configure via the evice’s web
pages. SSL must be enable before setting up either SNMPv3 or IPSec. SSL must also be enable in or er to use any
of the Web Services (Automatic Meter Rea s, or Network Scanning Vali ation Service).
SSL shoul be enable so that the evice can be securely a ministere from the web UI. When scanning, SSL can be
use to secure the filing channel to a remote repository.
SSL uses X.509 certificates to establish trust between two en s of a communication channel. When storing scanne
images to a remote repository using an https: connection, the evice must verify the certificate provi e by the
remote repository. A Truste Certificate Authority certificate shoul be uploa e to the evice in this case.
To securely a minister the evice, the user’s browser must be able to verify the certificate supplie by the evice. A
certificate signe by a well-known Certificate Authority (CA) can be ownloa e to the evice, or the evice can
generate a self-signe certificate. In the first instance, the evice creates a Certificate Signing Request (CSR) that
can be ownloa e an forwar e to the well-known CA for signing. The signe evice certificate is then uploa e
to the evice. Alternatively, the evice will generate a self-signe certificate. In this case, the generic Xerox root CA
certificate must be ownloa e from the evice an installe in the certificate store of the user’s browser.
The evice supports only server authentication.
2.8.2.12. Port 515, LPR
This is the stan ar LPR printing port, which only supports IP printing. It is a configurable port, an may be explicitly
enable or isable in the Properties tab of the evice’s web pages.
2.8.2.13. Port 546, DHCPv6
This port is use only when performing DHCPv6, an is not open all of the time. To permanently close this port,
DHCPv6 must be explicitly isable . This is one via the TCP/IP page in the Properties tab on the WebUI.
2.8.2.14. Port 631, IPP
This port supports the Internet Printing Protocol. It is not configurable. This is isable when the http server is
isable .

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2.8.2.15. Port 636, sLDAP
This is the stan ar LDAP port when using SSL for a ress book queries in the Scan to Email feature.
2.8.2.16. Port 1124, Network Scan Utility
This port supports the Xerox Network Scan utility. It is not configurable an cannot be isable .
2.8.2.17. Port 1900, SSDP
This port behaves similarly to the SLP port. When activate , this port is use for service iscovery an a vertisement.
The evice will a vertise itself as a printer an also listen for SSDP queries using this port. It is not configurable. This
port is explicitly enable / isable in the Properties tab of the evice’s web pages.
2.8.2.18. Port 3003, http/SNMP reply
This port is use when the http server requests evice information. The user isplays the Web User Interface
(WebUI) an goes to a page where the http server must query the evice for settings (e.g. Novell network settings).
The http server queries the machine via an internal SNMP request (hence this port can only open when the http
server is active). The machine replies back to the http server via this port. It sen s the reply to the loopback a ress
(127.0.0.0), which is internally route to the http server. This reply is never transmitte on the network. Only SNMP
replies are accepte by this port, an this port is active when the http server is active (i.e. if the http server is isable ,
this port will be close ). If someone attempte to sen an SNMP reply to this port via the network, the reply woul
have to contain the correct sequence number, which is highly unlikely, since the sequence numbers are internal to the
machine.
2.8.2.19. Port 5200, UPnP
This port is use by UPnP. This is isable when SSDP is isable (see 3.2.2.16).
2.8.2.20. Port 5353, Multicast DNS
Designating a Multicast DNS server will allow the evice to resolve omain names over a multicast protocol. This can
be configure via the Local UI or WebUI.
2.8.2.21. Port 6000, SetIP Utility
This port supports the Xerox SetIP utility. It is not configurable an cannot be isable .
2.8.2.22. Port 9100, raw IP
This allows ownloa ing a PDL file irectly to the interpreter. This port has limite bi- irectionality (via PJL back
channel) an allows printing only. This is a configurable port, an may be isable in the Properties tab of the
evice’s web pages.
2.8.2.23. 9400, TWAIN for Network Utility
This port supports the Xerox TWAIN for Network utility. It is not configurable an cannot be isable .
2.8.2.24. 9401, TWAIN for Network Utility
This port supports the Xerox TWAIN for Network utility. It is not configurable an cannot be isable .
2.8.3. IP Filtering
The evices contain a static host-base firewall that provi es the ability to prevent unauthorize network access
base on an IP a ress or IP a ress range. Filtering rules can be set by the SA using the WebUI.