Zycoo CooVoox U20 2 FXO 30Extension ,4GB IP PBX System

Call Features
Call Back
Call Forward
Call Hold
Call Paging and Intercom
Call Park
Call Pickup
Call Queue
Call Recording
Call Routing
Blind Transfer 
Attended Transfer
Call Waiting
Caller ID
Dial by Name
Music On Hold/Transfer
3-Way Conference
Video Call

PBX Features
Black List
BLF (Busy Lamp Field)
CDR (Call Detailed Record)
Conference Room (3 Rooms)
Call Monitoring
DID (Direct Inward Dialing Number)
DISA (Direct Inward System Access)
Distinctive Ringtone
DND (Do Not Disturb)
DNIS (Dialed Number Identification Service)
Feature Codes
FOP (Flash Operation Panel) Status Monitoring
Follow Me
IVR (Interactive Voice Responses)
Mobility Extension
Multi-Language Prompts
Multi-Language GUI 
One Touch Recording
Phone Book
Phone Provisioning
Pin Set
Record File Download
Ringgroup
SIP Register with UDP/TCP/TLS
SIP Trunk 
Skype for SIP
Smart DID
Speed Dial
Spy
SRTP (Secure Realtime Transport Protocol)
T.38 Fax (Pass-through)
Time Based Rule
Virtual Fax Voicemail & Voicemail to Email

System Capacities
10 Concurrent Calls
Up to 30 IP Phone Registers/Extensions
Recording: 21,000 mins (.gsm); 3,000 mins (.wav)
Voicemail: 21,000 mins (.gsm); 3,000 mins (.wav)

Codecs & Protocols
Audio Codecs: G.722/G.711-Ulaw/G.711-Alaw/G.726/G.729/GSM/SPEEX
Video Codecs: H.261/H.263/H.263+/H.264
Protocols: SIP (RFC3261)/IAX2 
DTMF: RFC2833/SIP INFO/In-Band

Network Features
DDNS Client 
DHCP Server
IPv4/IPv6/IEEE802.1Q
IP Assignment (PPPoE/DHCP/Static)
SNMP v1/v2
TR069
Static Route Table
Trouble Shooting (Ping/Traceroute)
PoE (Power over Ethernet)
VPN Client (N2N/L2TP/PPTP/OpenVPN)
VPN Server (PPTP/L2TP/OpenVPN, Up to 10 Users)

Security Features
Refuse SIP Register DoS
Refuse Abort Invite DoS
Refuse SSH Login DoS
Firewall

Logs
PBX Log
Web Access Log
PBX Debug Log