My download/upload in server and out of server is too slow (around 50 KB/s !) !

Did I miss some configuration ?

Some information:

CentOS release 6.3

uptime

load average: 0.17, 0.32, 0.37

Memory

free -m
             total       used       free     shared    buffers     cached
Mem:         24009      21988       2021          0        806      18098
-/+ buffers/cache:       3083      20926
Swap:         4095         28       4067


lshw -C network
  *-network               
       description: Ethernet interface
       product: 82574L Gigabit Network Connection
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: eth0
       version: 00
       serial: 00:25:90:70:17:4a
       size: 100MB/s
       capacity: 1GB/s
       width: 32 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
       configuration: autonegotiation=off broadcast=yes driver=e1000e driverversion=1.9.5-k duplex=full firmware=2.1-2 ip=108.175.8.123 latency=0 link=yes multicast=yes port=twisted pair speed=100MB/s
       resources: irq:16 memory:fb900000-fb91ffff ioport:e000(size=32) memory:fb920000-fb923fff

ethtool

ethtool eth0
Settings for eth0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full 
                                100baseT/Half 100baseT/Full 
                                1000baseT/Full 
        Supports auto-negotiation: Yes
        Advertised link modes:  Not reported
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Speed: 100Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: off
        MDI-X: off
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00000001 (1)
        Link detected: yes

dmesg |grep e1000e

dmesg |grep e1000e
e1000e: Intel(R) PRO/1000 Network Driver - 1.9.5-k
e1000e: Copyright(c) 1999 - 2012 Intel Corporation.
e1000e 0000:02:00.0: Disabling ASPM L0s 
e1000e 0000:02:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
e1000e 0000:02:00.0: setting latency timer to 64
e1000e 0000:02:00.0: irq 33 for MSI/MSI-X
e1000e 0000:02:00.0: irq 34 for MSI/MSI-X
e1000e 0000:02:00.0: irq 35 for MSI/MSI-X
e1000e 0000:02:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:25:90:70:17:4a
e1000e 0000:02:00.0: eth0: Intel(R) PRO/1000 Network Connection
e1000e 0000:02:00.0: eth0: MAC: 3, PHY: 8, PBA No: FFFFFF-0FF
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e 0000:02:00.0: eth0: Unsupported Speed/Duplex configuration
e1000e: eth0 NIC Link is Up 10 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e 0000:02:00.0: Disabling ASPM  L1
e1000e 0000:02:00.0: eth0: changing MTU from 1500 to 9000
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO
e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
e1000e 0000:02:00.0: eth0: 10/100 speed: disabling TSO