diff --git a/aprslib/IS.py b/aprslib/IS.py
index fc0d16b..8f99d62 100644
--- a/aprslib/IS.py
+++ b/aprslib/IS.py
@@ -127,6 +127,31 @@ class IS(object):
         if self.sock is not None:
             self.sock.close()
 
+    def sendall(self, line):
+        """
+        Send a line, or multiple lines sperapted by '\\r\\n'
+        """
+        if not self._connected:
+            raise ConnectionError("not connected")
+
+        if isinstance(line, unicode):
+            line = line.encode('utf8')
+        elif not isinstance(line, str):
+            line = str(line)
+
+        if line == "":
+            return
+
+        line = line.rstrip("\r\n") + "\r\n"
+
+        try:
+            self.sock.setblocking(1)
+            self.sock.settimeout(5)
+            self.sock.sendall(line)
+        except socket.error as exp:
+            self.close()
+            raise ConnectionError(str(exp))
+
     def consumer(self, callback, blocking=True, immortal=False, raw=False):
         """
         When a position sentence is received, it will be passed to the callback function
diff --git a/tests/test_IS.py b/tests/test_IS.py
index 186d043..b7aa382 100644
--- a/tests/test_IS.py
+++ b/tests/test_IS.py
@@ -7,7 +7,7 @@ import sys
 import os
 
 
-class TestCase_IS(unittest.TestCase):
+class TC_IS(unittest.TestCase):
     def setUp(self):
         self.ais = aprslib.IS("LZ1DEV-99", "testpwd", "127.0.0.1", "11111")
         self.m = mox.Mox()
@@ -260,8 +260,61 @@ class TestCase_IS(unittest.TestCase):
 
         self.m.VerifyAll()
 
+    def test_sendall(self):
+        self.ais.sock = mox.MockAnything()
+        self.m.StubOutWithMock(self.ais, "close")
 
-class TestCase_IS_consumer(unittest.TestCase):
+        # part 1 not connected
+        #
+        # part 2 socket.error
+        self.ais.sock.setblocking(mox.IgnoreArg())
+        self.ais.sock.settimeout(mox.IgnoreArg())
+        self.ais.sock.sendall(mox.IgnoreArg()).AndRaise(socket.error)
+        self.ais.close()
+        # part 3 empty input
+        #
+
+        mox.Replay(self.ais.sock)
+        self.m.ReplayAll()
+
+        # part 1
+        self.ais._connected = False
+        with self.assertRaises(aprslib.ConnectionError):
+            self.ais.sendall("test")
+        # part 2
+        self.ais._connected = True
+        with self.assertRaises(aprslib.ConnectionError):
+            self.ais.sendall("test")
+
+        # part 3
+        self.ais._connected = True
+        self.ais.sendall("")
+
+        # verify so far
+        mox.Verify(self.ais.sock)
+        self.m.VerifyAll()
+
+        # rest
+        self.ais._connected = True
+        for line in [
+                "test",      # no \r\n
+                "test\r\n",  # with \r\n
+                u"test",     # unicode
+                5,           # number or anything with __str__
+                ]:
+            # setup
+            self.ais.sock = mox.MockAnything()
+            self.ais.sock.setblocking(mox.IgnoreArg())
+            self.ais.sock.settimeout(mox.IgnoreArg())
+            self.ais.sock.sendall("%s\r\n" % str(line).rstrip('\r\n')).AndReturn(None)
+            mox.Replay(self.ais.sock)
+
+            self.ais.sendall(line)
+
+            mox.Verify(self.ais.sock)
+
+
+class TC_IS_consumer(unittest.TestCase):
     def setUp(self):
         self.ais = aprslib.IS("LZ1DEV-99")
         self.ais._connected = True